'm 


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Cumnr^iings  School  of  Veterinary  iVledicine  at 
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^jt,^L^.: 


EXPLANATION   OF   FIGURE  I. 


OSSEOUS  STR 

1. 

Frontal  bone. 

2. 

Parietal. 

3. 

Occipital. 

4. 

Temijoral. 

5. 

Nasal. 

6. 

Laclu-ynial. 

7. 

Malar. 

8. 

Superior  maxillary. 

9. 

Anterior         " 

10. 

Liferior          " 

11. 

Cer\acal  vertebrae. 

33. 

Scapula. 

34. 

Hmnerus. 

From  4  to  7  is  the  zjgomatic  arch. 

MUSCLES   OF  THE   HEAD,   NECK,   AND   SHOULDER. 


* 

Ligamentum  colli. 

a". 

Trapezius. 

6". 

Rhomboideus  longus. 

c". 

Scalenus. 

e". 

Sterno  scapulari  —  pectoralis  transversus. 

/"■ 

,  Antea  spinatus. 

f- 

Postea  sjoinatus. 

W. 

Teres. 

c. 

Dilator  naris  lateralis. 

d. 

"           "      anterior. 

e. 

Orbicularis  oris. 

/• 

Nasalis  longus. 

9- 

Levator  labii  superioris. 

Ti. 

Buccinator. 

i. 

Zygomaticus. 

J- 

Retractor  labii  inferiorus. 

k. 

Masseter. 

I 

Abducens  aurem. 

m. 

Attolentes  et  adducens  am-em. 

n. 

Retrahentes  aurem. 

0. 

Adducens  vel  deprimens  aurem. 

P- 

r.  Tendon  of  the  splenius  and  complexus  major. 

2- 

Obliquus  capitis  superior. 

s. 

Splenius. 

t. 

Obliquus  capitis  inferiorus, 

u. 

Levator  humeri. 

V. 

Sterno  maxillaris. 

X. 

Subscapulo-hyoideus. 

VEINS. 

1. 

Temporal  vein. 

2. 

Facial  vein. 

3. 

Jugular  vein. 

10. 

Parotid  gland. 

THE 


^N^TOMY     A.ND     I^HYSIOLOaiT 


THE  HORSE: 


ANATOMICAL    AND   QUESTIONAL    ILLUSTRATIONS, 


CONTAINING,   ALSO, 

A  SERIES  OF  EXAmNATIONS  ON  EQUINE  ANATOMY  AND  PHYSIOLOGY,  WITH  INSTRUC- 
TIONS m  REFERENCE   TO   DISSECTION,  AND   THE  MODE   OF  MAILING 
ANATOMICAL  PREPARATIONS. 


TO    WHICH    IS   ADDED, 

dllossHrg  of  ^fleriitarg  ^uhjxunlitks,  S^omologkal  €^mt,  aitb  ^idionarg  of  ^tttmxnxv  §^ntmt. 


GEORGE   H.   DADD,   M.  D.,   V.  S., 

AUTHOR  OF  "the  MODERN  HORSE  DOCTOR,"  "CATTLE  DOCTOR,"  ETC.,  ETC. 


BOSTON: 

PUBLISHED    BY   JOHN   P.   JEWETT   AND    COMPANY 

CLEVELAND,  OHIO :    H.  P.  B.  JEWETT, 

NEW  YORK:    SHELDON,  BLAKEMAN  AND  COMPANY. 

1857. 


Entered  according  to  Act  of  Congress,  in  the  year  1856,  by 

JOHN  P.  JEWETT  AND  COMPANY, 

In  the  Clerk's  Office  of  the  District  Court  of  the  District  of  JIassachusetta. 


UTUOTTPED   BT   TIIE   AMERICAN   STEREOTYPE   COMPANY, 
PUCENIX   BUILDING,    BOSTON. 


PREFACE. 


American  Veterinary  Literature  has  hitherto  possessed  no  work  devoted  to 
the  o.natomy  and  physiology  of  the  Horse;  consequently  such  subjects  are 
either  discussed  theoretically  and  imperfectly,  or  else  fail  to  be  noticed.  But 
a  new  era  is  now  dawning  upon  Veterinary  Science ;  a  spirit  of  inquiry  is 
abroad;  and  the  people  of  this  Repubhc  find  themselves  in  possession  of  some 
of  the  most  magnificent  specimens  of  "live  stock"  to  be  found  in  the  world. 
The  natural  inquiry  is,  "How  shall  we  protect  our  property?"  And  the 
conclusion  arrived  at  is,  "Veterinary  science  offers  the  only  probable  and 
practicable  security  against  the  numerous  casualties  incidental  to  the  Jiahitats 
of  the  ham  and  stable'^ 

Hitherto,  much  indifference  has  been  manifested  regarding  this  science,  in 
consequence  of  the  difficulty  encountered  in  its  study,  for  want  of  proper 
text-books  and  teachers ;  and  its  unsatisfactory  results  when  tested  by  men 
unacquainted  with  its  fundamental  principles.  The  Avell-known  works  of 
Enghsh  and  French  authors  furnish  all  the  necessary  information,  yet  their 
cost  is  beyond  the  means  of  many,  and,  therefore,  their  circulation  is  very 
limited. 

In  view,  therefore,  of  supplying  the  above  deficiency,  which  is  disclosed  in 
the  barrenness  of  our  anatomical  and  physiological  knowledge,  and  for  the 
purpose  of  furnishing  a  work  that  shall  come  within  the  reach  and  financial 
means  of  all  men,  the  author  has  undertaken  the  double  task ;  and  it  is  hoped 
that  the  effort  will  not  be  thought  untimely. 

There  are  a  vast  number  of  highly  educated  physicians  in  this  country 
who  are  often  urged  by  their  employers  to  give  advice  in  the  management, 
medical  and  surgical  treatment,  of  the  inferior  orders  of  creation  ;  yet  decline 
to  do  so,  in  consequence  of  a  lack  of  authoritative  knowledge  regarding 
anatomy,  physiology,  therapeutics,  and  pathology.  To  such,  whose  sympathies 
lean  in  the  right  direction,  and  who  are  willing  to  give  counsel,  and  lend  a 
helping  hand  in  the  restoration  of  a  sick  or  dying  animal,  this  work  is  offered, 
and  the  author,  therefore,  submits  it  to  their  candid  perusal  and  criticism. 

The  work,  however,  is  jorincipally  intended  for  veterinary  surgeons,  teachers 
of  the  art,  and  students  of  veterinary  medicine,  whose  wants  the  author 
professes  to  have  some  knowledge  of;  and  he  has  endeavored,  to  the  best  of 
his  abihty,  to  cater  to  the  same. 

The  necessity  for  such  a  work,  at  the  present  time,  is  evident  from  the  facts, 
that  three  veterinary  colleges  have  lately  come  into  legislative  existence,  and 

(in) 


IV  PEEFACE. 

it  is  very  natural  to  suppose  that,  ere  long,  many  candidates  for  the  honors  of 
these  institutions  will  knock  at  the  door  of  science,  and  seek  admittance  ;  they 
must  then  need  text-hooks ;  and,  in  view  of  furnishing  a  part  of  what  the  author 
foresees  every  teacher  and  student  must  necessarily  need,  he  offers  this,  not  as 
a  work  pregnant  with  his  own  ideas,  for  that  were  presumj)tuous,  when  anat- 
omy and  physiology  are  the  texts ;  but,  as  a  work  carefully  prepared  from  the 
writings  of  our  best  authorities,  the  work  may  be  considered  as  the  legitimate 
offspring  of  scientific  observation  and  experience. 

Another  argument  in  favor  of  the  necessity  that  will  soon  exist  for  a  text- 
book of  anatomy  and  physiology  is  founded  on  the  fact,  that  agricultural 
colleges  will  soon  be  endowed  in  every  State  of  the  Union ;  many  ^ready 
exist;  and  each  will,  probably,  endow  a  professorship  of  veterinary  science. 
With  such,  and  among  the  young  and  aged  men  that  may  seek  for  knowledge^ 
the  author  hopes  that  his  work  may  find  favor;  and,  if  such  should  be  the  result, 
he  will  have  the  satisfaction  of  knowing  that  he  has  not  labored  in  vain. 

There  are  other  classes  of  men  that  need  a  work  of  this  description;  namely, 
the  husbandman,  the  horse-owner,  and  the  horse-lover,  as  well  as  the  purely 
scientific  man.  The  three  first,  incited  by  laudable  sentiments,  or  pecuniary 
motives,  will  read  the  following  pages,  and  study  the  anatomical  illustrations ; 
some  with  veneration  of  that  wonderful  piece  of  mechanism,  a  horse's  structure ; 
others  for  the  purpose  of  making  themselves  acquainted  with  the  form,  action, 
and  capacities  of  the  same. 

The  piirelf/  scientific  man,  who  desires  to  inform  himself  how  veterinary 
science  is  to  be  studied,  —  what  are  its  legitimate  objects,  and  its  appropriate 
sphere,  —  will  read  these  pages  with  considerable  profit. 

GEORGE  H.  DADD. 

Boston,  January,  1857. 


REMARKS  IN  REGARD  TO  THE  COMPOSITION  OF  THIS  WORK. 


The  plan  of  the  author,  in  the  commencement  of  this  work,  was  to  prepare  a 
complete  manual  of  examinations  on  the  Anatomy  and  Physiology  of  the  Horse ; 
but,  finding  that  he  could  not  bring  the  matter  within  the  prescribed  limits,  the 
plan  was  speedily  abandoned.  The  examinations,  excepting  those  descriptive 
of  the  osseous  structure,  are  intended,  either  to  elicit  some  physiological  fact, 
or  to  introduce  topics  that  have  not  been  treated  of  in  the  body  of  the  work. 

In  attempting  to  furnish  the  public  with  a  systematic  treatise  on  Anatomy 
and  Physiology,  it  will  be  obvious  that  the  author  must  necessarily  avail 
himself  of  the  labor  of  others ;  for,  as  regards  the  science  of  anatomy,  no  one 
has  anything  new  to  offer.  The  industrious  anatomists  and  dissectors  of  early 
times  have  borne  off  all  the  laurels,  and  there  remains  but  httle,  if  anything, 
for  future  discovery.  As  regards  physiology,  also,  there  are  very  few  facts  to 
discover;  we  now  allude,  however,  to  practical  physiology — that  science  which 
teaches  us  the  functions  of  the  animal  body,  or  the  uses  of  its  parts.  The 
author  has,  however,  occasionally  stepped  beyond  the  details  of  practical 
physiology,  and  has  endeavored  to  throw  some  light  on  the  complex  combina- 
tions in  which  vital  phenomena  present  themselves,  and  the  nature  of  their 
dependencies  one  upon  another.  Matter  of  this  kind  he  has  thought  best  to 
introduce  in  the  form  of  examinations. 

In  preparing  this  work,  the  author  has  endeavored  to  select  the  most  recent 
and  reliable  information.  The  following  list  of  authors  consulted  and  com- 
piled from,  together  with  the  foot  notes  and  the  writers'  names  appended,  Avill 
serve  to  indicate  the  principal  sources  on  which  the  author  has  relied  for 
information. 

Mr.  Percivall's  Anatomy  of  tJie  Horse  has  been  freely  employed  in  composing 
the  anatomical  part  of  the  work.  The  description  of  the  abdominal  viscera 
is  from  the  pen  of  Mr.  Gamgee,  and  was  written  as  a  prize  essay,  and  pub- 
lished in  the  London  Veterinarian.  Carpenter's  Physiologif,  general  and  compar- 
ative, is  also  quoted.  Liebig's  Chemistry,  Hooper's  Dictionary,  Percivall's  Hippor 
pathology,  Roget's  Outlines  of  Physiology,  have  also  been  consulted,  and  extracts 
made  from  the  same.  The  illustrations,  not  otherwise  indicated,  are  by  Girard; 
explanations  translated  by  the  author.  For  the  loan  of  the  French  plates,  the 
author  is  indebted  to  C.  C.  Grice,  V.  S.,  of  New  York  City. 

The  plan  of  the  examimdions  was  suggested  to  the  author  by  Ludlow's  Manual 
of  Examinations, —  a  work  which  he  formerly,  while  studying  medicine,  had 
occasion  to  use.  The  subject  matter,  in  this  work,  of  course  diflers  from  that  of 
the  former. 

In  preparing  the  "Definitions  of  Veterinary  Technicalities,"  and  "Diction- 
ary," the  author  has  availed  himself  of  the  works  of  Cooper,  Hooper,  Cleve- 
land, Blaine,  Mahew,  and  White ;  and,  regarding  the  method  of  making  ana- 
tomical preparations,  etc.,  the  works  of  Parsons,  Pope,  and  Swan,  have  been 
consulted.  G.  H.  D. 


CONTENTS. 


PASE 

Preface, - 3 

Remarks  regarding  the  composition  of  the  work,       ----------  5 

Remarks  on  the  osseous,  cartilaginous,  and  ligamentous  structures,  ------  H 

Tegumentaey  System.  —  On  the  hair  of  horses  ;  examinations  on  the  common  integument;  physiol- 
ogy of  the  skin,  of  the  cellular  membrane,  of  the  adipose  tissue ;  examinations  on  the  same,  14-17 
Of  tiie  External  Parts.  —  The  hoof;  its  form,  spread,  color,  magnitude  ;  the  wall;  its  situation  and 
relation,  connection,  figure,  division,  solar  border,  laminse,  quarters,  heels,  coronary  border  and 
bars,             __>_-_----------         17-23 

The  Sole.  —  Situation  and  connection,  figure,  arch,  division,  surfaces,  and  thickness,  -        -  23-25 

The  Frog.  —  Its  situation  and  connection,  figure,  division,  surfaces ;  the  cleft  of  the  frog,  its  supe- 
rior surface,  the  sides,  the  commissures,  toe,  heels  or  bulb,  coronary  frog  band ;  development  of 
hoof;  structure  of  the  hoof ;  production  of  the  hoof;  properties  of  horn,        -        _        -        -  25-30 

Internal  Parts  of  the  Hoof.  —  The  coronary  substance  ;  its  situation,  connection,  structure,  and 

organization,  ____--__-------       30-31 

The  Cartilages.  —  Their  situation,  attachment,  and  form ;  the  false  cartilages,  and  their  use ;  the 
sensitive  laminae ;  division  of  the  same ;  elasticity,  number,  dimensions,  and  organization  ;  the 
sensitive   sole ;  its  structure,  connection,  thickness,  and   organization ;  the   sensitive   frog ;  its 
situation,  division,  structure,  and  organization,       ---------  31-34 

A  tabular  view  of  the  bones  of  the  horse,  ----------  35 

Anatomy  of  the  skeleton,  introduced  in  the  form  of  questions  and  answers,  embracing  a  complete 

system  of  osteology,    --------------  36-54 

Remarks  on  the  changes  which  horses'  teeth  undergo,  with  examinations  on  the  same,        -        -  54-56 

Myology. — A  table  of  the  names  and  number  of  muscles,  divided  into  regions,  -         .        -  57-60 

A    tabular  synopsis  of  the    number,  name,   region,    situation,  insertion,  and  action   of   all    the 

muscles,        ----------------        61-78 

On  Dissection.  —  Dissecting  instruments;   subjects  suitable  for  dissection;   rules  in  reference  to 

dissection  of  muscles,  _-------__-.--  79-80 

Anatomical  Preparations. —  Injecting  instruments;  directions  for  using  the  syringe,  -  80-81 

On  the  Different  kinds  of  Injections.  —  Formulae  for  coarse  warm  injections  ;  fine  injections; 
minute  do;  plaster  injection;  cold  injection;  as  regards  the  course  of  injections ;  quicksilver 
injections;  mode   of  injecting  the  lymphatics   with  quicksilver;  method  of  injecting  the  lac- 
teals,  and  parotid  gland ;  wet  preparations  ;  preparations  by  distension  ;  method  of  preparing 
and  distending  the  lungs ;  menstrua  for  preserving  specimens  ;  method  of  preserving  the  brain 
and  lungs ;  method  of  macerating  and  cleaning  bones ;  to  render  bones  flexible  and  transpa- 
rent; method  of  cleaning  and  separating  the  bones  of  the  cranium;  exposition  of  Mr.  Swan's 
new  method  of  making  dry  anatomical  preparations,   *-------  81-87 

Digesti\^  System.  —  The  mouth,  lips,  cheeks,  gums,  palate,  tongue,  salivaiy  glands,  pharynx, 
oesophagus,  and  nasal  fossa ;  cavity  of  the  cranium ;  tlie  orbits  and  cavities  of  the  nose ;  the 
mouth,  peritoneum,  stomach,  intestines ;  the  vessels,  nerves,  and  lymphatics  of  the  intestines ; 
the  spleen,  liver,  pancreas,  kidneys,  supra,  renal  capsules,  vu-eters,  bladder,  urethra,  -  -  87-119 
Generative  Organs  of  the  Male.  —  Vasa  deferentia,  vesiculse  seminales,  ejaculatory  ducts,  pros- 
trate gland,  Cowper's  glands,       --- ..-.      119-121 

Organs  of  Generation  Contdjued.  —  Testicles  and  scrotum,  spermatic  cord,  epididymis,  penis, 

and  urethra, __--..-  121-125 

Female  Organs  of  Generation, 125-128 

Physiological  considerations  on  the  reproduction  of  organized  beings, 128-136 

Examination  on  the  digestive  system,  -...-------       136-138 

Remarks  and  examinations  on  the  eye, 139-143 

(vii) 


viii  '  CCfNTENTS, 

Respir.\tory  System.  —  Observation   on  the  same ;  the  larjiix,  glottis,  epiglottis,  tracliea,  bron- 
chial tubes,  pleura,  mediastinum,  lungs,  broncliial  glands, 144-154 

CmcuLATonY  System.  —  Remarks  on  the  blood ;  examinations  resumed  on  the  blood,  pericardium, 

and  heart, 155-157 

Arterlvl  System. — Distribution  of  the  arteries,  15^163 

A  table  showing  the  modes  of  the  distribution  of  the  arteries, 1G4-166 

Distribution  of  the  veins, 166-168 

A  table  showing  the  mode  of  distribution  of  the  veins, 169-170 

The  brain  and  its  appendages ;  the  nervous  system, 171-177 

Examinations  on  neurology,  .....-------  177-180 

Distribution  of  the  lymphatics, 181-184 

A  glossary  of  veterinary  technicalities, 185-193 

Toxicological  chart, 195-209 

A  dictionary  of  veterinary  science, 211-287 

Appendix. —  Ligamcntary  mechanism  of  articulations  and  joints,  289-291 


INDEX  OE  THE  ILLUSTRATIONS. 


FIGURE  I.  — Presents  two  views  :  one  of  a  portion  of  the  osseous  structure,  showing  the  head,  neck, 
and  shoulders ;  and  the  other  is  comi30sed  of  the  superficial  muscles,  covering  the  above  parts ; 
precedes  the  title  page.      ----------_.__ 

FIGURE  II.  —  Is  a  section  of  the  osseous  structm-e,  giving  a  side  of  the  spinal  column,  ribs,  and  a  part 

of  the  rear,  anterior,  and  posterior  extremities.       ----...__  jq 

FIGURE  III.  —  Is  a  representation  of  the  superficial  muscles  of  the  body,  of  a  part  of  the  neck,  and 

of  the  extremities,      -_----------___         20 

FIGURE  rV.  —  Has  four  illustrations  of  the  hind  extremities,  as  follows  :  No.  1  is  a  side  view  of  the 
bones  of  the  ofl-hiud  leg ;  No.  2  shows  the  muscles  and  tendons  of  the  off-hind  leg ;  No.  3  is  a 
front  view  of  the  bones  of  the  same  ;  No.  4  shows  the  muscles  and  tendons  in  the  anterior  region, 
or  front  part,  of  the  off-liind  extremity.  -_--______  30 

FIGURE  V. — Presents  two  illustrations  :  the  first  shows  the  supei-ficial  muscles  in  the  region  of  the 
head,  neck,  and  shoulders,  on  the  near  side  ;  and  the  other  is  a  corresponding  section  of  the  osse- 
ous structure,  on  which  the  insertions  of  the  ligamentum  colli  into  the  occiput,  cer\ical  vertebrte, 
and  dorsal  spines,  are  sho-rni.      -------._-___         40 

FIGURE  VI.  —  Presents  four  views  of  the  forward  extremities  :  No.  1  shows  the  bones  which  enter 
into  the  composition  of  the  near  fore-leg ;  No.  2  is  a  side  view  of  the  muscles  and  tendons  of  the 
near  fore-leg ;  No.  3  is  an  anterior  view  of  No.  1 ;  No.  4  is  an  anterior  view  of  No.  2.       -        -  50 

FIGURE  Vn.  —  Presents  four  views  of  the  near  fore-extremity :  Nos.  1  and  3  are  side  and  posterior 
views  of  the  bones  of  the  near  fore-limb ;  Nos.  2  and  4  show  the  muscles  and  tendons  belonging 
to  the  above  regions.  ---.--_-__.        ...qq 

FIGURE  VIII.  —  Has  four  views  of  the  off"-hind  extremity :  Nos.  1  and  3  are  side  and  posterior  views 
of  the  bones  entering  into  the  composition  of  the  Hnib ;  Nos.  2  and  4  show  the  muscles  and  ten- 
dons of  the  same.  ------..._._-_  70 

FIGURE  IX.  — Presents  two  views  :  one,  of  the  bones  ;  the  other  shows  the  superficial  muscles  of  the 

head,  neck,  shoulders,  and  breast,  viewed  in  an  anterior  dh-ection.  -----         80 

FIGURE  X.  —  Has  two  cuts  :  one   of  wliich  shows  a  portion  of  the  osseous  framework ;  the  other 

shows  the  superficial  muscles  belonging  thereto.       ---.-____  99 

FIGURE  XI.  —  Is  illustrated  by  two  cuts  :  one  of  which  shows  a  portion  of  the  muscles  of  the  body, 
neck,  and  Hmbs  ;  it  is  a  sort  of  anterior  side  view ;  the  second  cut  shows  the  bones  which  enter  into 
the  comjwsition  of  these  parts.  --------.._.       loO 

FIGURE  Xn.  — Has  two  illustrations,  which  aretlie  counterpart  of  Fig.  XL,  as  seen  from  the  oppo- 
site or  posterior  direction.       -        -        -        -        -        -        -        - 119 

FIGURE  XIH.  —  Presents  a  side  view  of  the  deep-seated  muscles :  it  is  taken  from  Mr.  Blaine's  "  Out- 

Hnes,"  and  is  one  of  the  most  magnificent  plates  ever  presented  to  the  public.       -        -        -        -       120 

FIGURE  XrV.  —  Is  a  \iew  of  the  muscles  and  tendons  of  the  fore  and  hind  extremities.  -        -  140 

FIGURE  XV.  — Is  illustrated  with  five  -siews  of  the  off  and  rear  fore  extremity :  Nos.  1,  2, 3  show  very 
distinctly  the  action  of  the  flexors  of  the  limb,  as  well  as  their  location,  and  that  of  the  extensor 
tendons  and  muscles.  The  triceps  extensor  brachii,  and  pectoral  muscles,  are  also  quite  ijromincnt 
and  easily  recognized ;  No.  4  is  the  same  hmb  divested  of  the  soft  parts ;  No.  5  is  an  interior  view 
of  the  near  fore-leg,  and  shows  some  of  the  tendons  and  muscles  wliich  are  not  seen  in  the  other 
cuts. - -        -         -       150 

FIGURE  XVI.  —  Presents  five  views  of  the  hind  extremities,  in  wliich  the  use  and  action  of  several  very 
important  muscles  and  tendons  are  accurately  delineated  :  Nos.  1,  2,  3,  4  compose  the  bones, 
muscles,  and  tendons  of  the  near-hind  extremity ;  No.  5  shows  the  muscles  and  tendons  on  the 

inside  of  the  near-hind  leg. 160 

2  (Lx) 


X  INDEX   TO   THE   ILLUSTRATIONS. 

FIGURE  XVn.  —  Presents  two  views  (as  seen  from  a  posterior  direction) :  one  contains  a  great  portion 
of  the  superficial  muscles  of  the  body  and  limbs,  and  the  other  shows  the  basis  of  their  super- 
structure. --_------.----._       170 

FIGURE  XVIII.  —  Is  the  skeleton  of  a  horse,  for  which  the  author  is  indebted  to  Blaine's  "  Outlines 

of  the  Veterinary  Art."  .        .        .        -        - 180 

FIGURE  XIX.  —  Is  a  counterpart  of  Fig.  XVn.,  as  seen  from  an  opposite  direction.  .        _        .       175 

FIGURE  XX.  —  Is  an  excellent  representation  of  the  muscles  of  one  side  of  the  head,  neck,  body,  and 

Hmbs. 211 

[The  author  considers  it  clue  to  himself  to  remark,  tliat,  in  consequence  of  not  securing  from  the  engi-aver  good  proofs  of 
the  plates,  there  will  occur  a  few  inaccuracies  between  the  lettering  on  the  cuts  and  explanations  accompanjnng  them. 
These,  however,  are  not  of  material  consequence ;  yet,  if  necessary,  the  reader  can,  from  analog}',  —  by  comparing  one  plate 
■with  another,  —  correct  the  errors  with  a  pen.] 


EXPLANATION   OF   FIGURE   II. 


OSSEOUS   STEUCTUKE. 

11. 

Cervical  vertebrae. 

12. 

Dorsal           " 

13. 

Lumbar        " 

14. 

Sacrum. 

15. 

Coccygeal  bones. 

16. 

True  ribs. 

17. 

False    " 

18. 

Sternum. 

19. 

Pelvis. 

20. 

Posterior  part  of  the  pehis,  or  ischiatic  spines, 

21. 

Inferior,  or  pubic  region. 

22. 

Femur. 

23. 

Patella. 

24. 

Tibia. 

33. 

Scajjula. 

34. 

Humerus. 

35. 

Radius. 

e. 

Fibula. 

/. 

Ulnar. 

REMARKS 


OSSEOUS,  CARTILAGINOUS,  AND  LIGAMENTOUS  STRUCTURES. 


The  bones  are  the  solid  framework  which 
gives  stability  to  the  whole  fabric,  and  af- 
ford fixed  bearings  upon  which  the  powers 
regulating  the  varied  movements  operate. 
The  bones,  then,  are  considered  as  the  most 
dense  and  solid  structures  of  the  animal 
frame :  affording  support,  and  in  many  parts 
protection,  .to  some  of  the  softer  parts ;  at 
the  same  time,  the  leverage  which  regulates 
the  action  of  a  limb  is  derived  from  the 
osseous  structure. 

On  making  an  examination  of  a  bone, 
we  find  that  its  external  surface  is  the  hard- 
est part,  and  it  differs  very  much  in  thick- 
ness in  different  bones,  and  in  different 
animals.  The  long  bones  (or  cylindrical) 
of  the  horse  contain  less  marrow,  and  are 
more  cancellated  within,  than  the  bones  of 
the  human  subject :  in  many  of  the  former 
the  whole  arena  is  ©ccupied  by  cancelli. 
The  bones  of  the  ribs  have  an  osseous  plat- 
ing differing  in  thickness  in  various  sub- 
jects, and  within  is  a  cellular  structure  which 
may  be  termed  diploe. 

The  marrow,  as  it  is  termed,  is  a  soft 
substance  of  an  oleaginous  character,  con- 
tained in  an  infinite  number  of  sacs,  depos- 
ited and  suspended  in  the  cavities  of  bones 
and  in  the  cancelli.  The  marrow  sacs  are 
composed  of  a  delicate  vascular  membrane, 
which  isolates  them  from  each  other,  and 
prevents  the  marrow  from  gravitating  or 
passing  into  the  osseous  structure. 

Bones  present  the  appearance  of  lamella, 
yet  they  are  fibrous ;  the  fibres  of  the  cylin- 
drical bones  are  longitudinal;  in  the  flat 
bones  they  have  a  radiated  appearance,  and 
in  the  short  and  peculiar  shaped  bones,  the 


fibrous  arrangement  is  more  irregular  and 
difficult  to  trace. 

The  basis  of  the  osseous  structure  is 
nearly  the  same  as  the  membranous  parts,* 
being  composed  of  fibrous  lamina?  or  plates, 
which  are  connected  together  so  as  to  form, 
by  their  intersection,  a  series  of  cells  anal- 
agous  to  those  of  the  cellnlar  structure. 
This  theory  has  been  disputed  by  some 
distinguished  physiologists ;  the  moderns 
contend  that  the  osseous  fabric  is  cellular.f 

Bones  are  invested,  on  their  exterior,  ex- 
cept those  parts  plated  with  cartilage,  with 
a  membrane  termed  periosteum.  Through 
this  medium  an  arterial  and  venous  com- 

*  "  The  analysis  of  a  bone  into  its  two  constituent  parts 
is  easily  effected  by  the  agency  either  of  acids  or  of  heat. 
By  macerating  a  full-grown  bone  for  a  sufficient  time  in 
diluted  muriatic  acid,  the  earthy  portion  of  the  bone, 
amounting  to  nearly  one-third  of  its  weight,  is  dissolved 
by  the  acid ;  the  animal  poition  only  remaining.  This 
animal  basis  retains  the  bulk  and  shape  of  the  original 
bone,  but  is  soft,  flexible,  and  elastic ;  possessing,  in  a 
word,  all  the  properties  of  membranous  parts,  and  corres- 
ponding in  its  chemical  character  to  condensed  albumen. 
A  portion  of  this  solid  animal  substance  aff"ords  gelatin  by 
long  boiling  in  water,  especially  under  the  pressure,  ad- 
mitting of  a  high  temperature,  to  which  it  may  be  sub- 
jected in  Papin's  digester.  On  the  other  hand,  by  sub- 
jecting a  bone  to  the  action  of  fire,  the  animal  part  alone 
will  be  consumed,  and  the  earth  left  untouched,  preserv- 
ing, as  before,  the  form  of  the  bone,  but  having  lost  the 
material  which  united  the  particles,  presenting  a  fragile 
mass  which  easily  crumbles  into  powder.  This  earthy 
basis,  when  chemically  examined,  is  found  to  consist  prin- 
cipally of  phosphate  of  lime,  which  composes  eighty-two 
hundredths  of  its  weight ;  and  to  contain  also,  according 
to  Berzelius,  minute  portions  of  fluate  and  carbonate  of 
lime,  together  with  the  phosphates  of  magnesia  and  of 
soda."  — Roget. 

t  The  best  authority  in  support  of  the  cellular  theory  is 
Scarpa.  Percivall  advocates  the  laminated  and  fibrous 
theories. 

(11) 


/ 


12 


ANATOMY    AND    PHYSIOLOGY   OF 


munication  is  established  between  the  dense 
and  soft  parts.  The  periosteum  is  anal- 
agous  to  the  fibrous  textures,  being  com- 
posed of  numerous  inelastic  fibres  of  great 
strength  and  density. 

The  inner  surface  of  the  periosteum  is 
connected  with  the  bone  by  the  vessels  pass- 
ing from  the  one  to  the  other,  and  also  by 
numerous  prolongations,  which  pervade  the 
osseous  substance. 

The  blood-vessels  of  the  periosteum  are 
numerous,  and  are  easily  demonstrated  by 
injection. 

CARTILAGE.* 

The  structure  which  appears  most  inti- 
mately connected  with  the  osseous  is  carti- 
lage. It  is  a  firm  and  dense  substance, 
apparently  homogeneous  in  its  texture,  semi- 
pellucid,  and  of  a  milk-white  or  pearly  color. 

The  surface  of  cartilage  is  smooth  and 
uniform,  presenting  neither  eminences  nor 
cavities,  pores  nor  inequalities.  It  has, 
however,  minute  capillary  vessels,  the  diam- 
eters of  which  are  too  small  for  ocular 
demonstration.  Notwithstanding  its  den- 
sity, it  has  a  minute  circulating  apparatus, 
which  is  demonstrated  in  diseases  known 
as  spavin  and  ringbone,  in  which  absorp- 
tion of  cartilage  occurs. 

Cartilaginous  structures  are  chiefly  com- 

*  "  The  mechanical  property  which  particularly  distin- 
guishes cartilage  is  elasticity,  a  quality  wliich  it  possesses 
in  a  greater  degree  than  any  other  animal  structure,  and 
which  adapts  it  to  many  useful  purposes  in  the  economy. 
Hence  it  forms  the  basis  of  many  parts  where,  contrary  to 
the  purposes  answered  by  the  bones,  pliancy  and  resistance 
as  well  as  firmness  are  required ;  and  hence  cartilage  is 
employed  when  a  certain  shape  is  to  be  preserved,  to- 
gether with  a  capability  of  yielding  to  an  external  force. 
The  flexibility  of  cartilage,  however,  docs  not  extend 
beyond  certain  limits  ;  if  these  be  exceeded,  fracture  takes 
place.  Great  density  bestowed  upon  an  animal  structure, 
indeed,  appears  to  be  in  all  cases  attended  with  a  propor- 
tionate degree  of  brittleness.  These  mechanical  proper- 
ties of  cartilages,  as  well  as  their  intimate  structure, 
although  nearly  homogenous  in  all,  are  subject  to  modifi- 
cation in  different  kinds  of  cartilage.  Cartilages  are 
covered  with  a  fine  membrane,  termed  the  perichondrium, 
analogous  in  its  structure  and  office  to  the  periosteum, 
which  we  have  already  had  occasion  to  point  out  among 
the  fibrous  membranes,  as  investing  the  bones."  — Ror/et. 


posed  of  gelatin,  albumen,  and  phosphate 
of  calcis. 

Cartilage  occurs  in  two  forms,  temporary 
and  permanent.  The  former  prevails  pre- 
vious to  adult  life ;  the  latter  are  identical 
with  the  permanent  structures  after  the 
animal  has  migrated  from  colthood. 

There  are  three  or  four  different  forms  of 
cartilages,  viz :  the  membriform,  interosseal, 
articular,  and  inter-articular. 

The  membriform  are  fibro-cartilaginous ; 
they  furnish  a  basis  of  support  to  the  softer 
parts,  supply  the  place  of  bone,  and  give 
form,  shape,  and  firmness,  to  parts  unossi- 
fied.  By  their  elasticity,  they  admit  of  con- 
siderable variation  of  figure  and  form,  yield 
to  external  pressure,  and  recover  their  proper 
shape  as  soon  as  pressure  is  removed.  This 
kind  of  cartilage  is  found  in  the  nostrils, 
ears,  larynx,  and  trachea. 

The  interosseal  cartilages  pass  from  one 
bone  to  another,  adhering  firmly  by  their 
extremities  to  each.  They  permit  of  an 
increase  of  extent  or  motion,  as  observed 
between  the  ribs  ;  when  macerated,  they  are 
divisable  into  laminae  of  an  oval  shape, 
which  are  united  by  fibres  passing  obliquely 
between  them. 

The  articular  cartilages  are  those  plates 
of  articular  substance  which  adhere  firmly 
and  inseparably  to  the  surfaces  of  bones 
which  are  opposed  to  each  other  in  the 
joints,  or  over  which  tendons  and  ligaments 
play.  The  elastic  resistance  of  this  carti- 
lage has  a  powerful  tendency  to  lessen  the 
shocks  incident  to  sudden  and  violent 
actions. 

The  inter-articular  cartilages  do  not  dif- 
fer in  composition  from  the  preceding. 
They  are  attached  to  the  inside  of  the  cap- 
sular ligament,  by  which  they  are  rendered 
somewhat  movable ;  and,  being  interposed 
between  the  bones  of  the  knee  and  hock, 
allow  them  a  greater  latitude  of  motion, 
while  at  the  same  time  they  contribute  to 
adapt  their  surfaces  more  perfectly  to  each 
other 
laminated 


The  structure  of  these  cartilages  is 


THE    HORSE. 


13 


FIBRO-CARTILAGINOUS     STRUCTURES. 

Fibro-cartilage  appears  to  be  of  an  in- 
termediate nature  between  ligament  and 
cartilage.  Having  a  fibrous  texture  united 
to  a  cartilaginous  basis,  it  combines  the 
characteristic  properties  of  both  of  the  above 
textures. 

Fibro-cartilaginous  structures  are  found 
to  unite  the  bodies  of  the  bones  of  the  ver- 
tebrae ;  they  then  get  the  name  of  inter- verte- 
bral substance.  They  impart  great  elasticity 
to  the  spine,  and  also  diminish  the  effects  of 
concussion. 

LIGAMENTOUS    STRUCTURES. 

The  ligamentous  structures  are  dense; 
possess  a  considerable  degree  of  solidity  in 
some  parts,  while  in  others  they  are  modi- 
fications of  fibrous  membrane.  The  liga- 
mentous system  includes  a  number  of  parts 
which  have  received  different  names,  such 
as  ligaments,  tendons,  faschia  aponeurosis, 
capsules  or  bursee  mucosa ;  and  fibres  of 
lisramentous  matter  also  enter  into  the  com- 
position  of  other  organs,  imparting  to  them 
different  degrees  of  mechanical  strength. 
The  ligamentous  structures  vary;  we  find 
that  in  some  places  they  are  expanded  into 
faschia,  etc.,  at  others  they  collect  into  dense, 
enlongated   cords.      The   first  division  in- 


cludes fibrous  membranes,  fibrous  capsules, 
tendinous  sheaths,  and  aponsurosis.- 

Fibrous  membranes :  these  resemble  or- 
dinary membranes,  only  that  their  fibres  are 
denser.  The  periosteum  is  a  membrane  of 
this  description,  and  the  dura  mater  has  a 
similar  structure. 

Fibrous  capsules  are  presented  in  the 
form  of  sacs,  which  surround  various  ten- 
dons and  joints.  These  capsules  are  also 
lined  by  a  synovial  membrane,  which  secretes 
the  synovia. 

Tendinous  sheaths  are  formed  by  fibrous 
membranes  which  surround  the  tendons,  in 
those  parts  that  are  subjected  to  friction,  or 
liable  to  displacement,  during  the  action  of 
the  muscles  which  move  the  joint. 

Aponeurosis  are  those  extended  sheets 
of  fibrous  texture  which  in  some  instances 
form  coverings  of  parts,  while  in  others 
they  constitute  points  of  attachment  to 
muscles.  In  the  former  case  they  are  termed 
faschiee,  and  either  surround  the  muscles  of 
a  limb,  forming  a  sheath  for  it,  or  else  invest 
or  confine  some  particular  muscle. 

In  the  latter  case  the  aponeurosis  presents 
broad,  or  narrow,  surfaces  and  fibres  which 
give  attachment  to  particular  portions  of 
muscle. 


ANATOMY    AND   PHYSIOLOGY. 


TEGUMENTARY  SYSTEM. 

ON    THE    HAIR    OF    HORSES. 

Hair  is  a  peculiar  tegumentary  appendage, 
characteristic  of  the  horse  and  other  rtiam- 
mals.  It  is  developed  on  the  interior  of 
ollicles  which  are  formed  by  a  depression  of 
the  true  skin.  These  follicles  are  lined  by  a 
continuation  of  the  epidermis,  the  cells  of 
which  are  developed  in  peculiar  abundance 
from  a  spot  at  its  deepest  portion ;  the  dense 
exterior  of  the  cluster  thus  formed  being 
known  as  the  bulb  of  the  hair,  while  the 
softer  interior  is  termed  its  pulp.  The 
elementary  parts  of  hair  are:  a  cortical  or 
investing  substance  of  a  dense  horny  tex- 
ture; and  a  medullary  or  pith-like  sub- 
stance, of  a  much  softer  character,  occupy- 
ing the  interior.  The  cortical  envelope  of 
hairs  is  a  continuation  of  the  outer  scaly 
layers  of  the  epidermis  that  lines  the  follicle ; 


whilst  the  medullary  is  derived  from  the 
deeper  stratum  whose  cells  are  produced  in 
unusual  abundance  at  the  coecal  extremity ; 
and  it  is  by  the  constant  development  of 
new  cells  at  this  point,  that  the  continual 
growth  of  the  hair  is  kept  up. 

An  excoriation  or  moulting  of  the  hair, 
which  falls  off,  is  replaced  by  a  new  growth, 
which  as  it  comes  to  maturity  assumes  the 


original  color. 


This  change  in  the  covering 


with  which  nature  has  so  wisely  clothed 
the  horse,  usually  takes  place  either  in  spring 
or  autumn,  or  at  both  periods.  The  hair 
of  the  mane  and  tail,  however,  is  not  sub- 
jected to  these  periodical  changes;  hence, 
it  acqukes  considerable  calibre  and  length. 

By  analysis,  the  hair  yields  carbon,  hy- 
drogen, nitrogen,  oxygen,  and  sulphur,  and 
its  variation  in  color  is  due  to  the  presence 
of  different  shades  of  matter  which  infil- 
trates the  cortical  substance. 


EXAMINATIONS   ON  THE   CO]\IMON  INTEGUMENTS. 


Q.  Of  how  many  parts  do  the  common  integuments 
consist  ?  —  A.  Three :  cuticle,  cutis,  and  rete  mucosum. 

Q.  Describe  the  cuticle  or  epidermis  ?  —  A.  It  is  a 
thin,  transparent,  tough,  and  elastic  jjorous  membrane, 
ser\ing  as  an  envelope  to  the  cutis,  or  true  sldn.  It  is 
composed  of  flexible  lamellae,  so  arranged  as  to  bear 
some  analogy  to  the  scales  of  lish ;  it  pervades  the 
whole  body,  and  insinuates  itself  into  jiorous  struc- 
tures and  follicular  passages,  inlets,  and  outlets  of  the 
system ;  it  is  supposed  to  be  continous  from  the  mouth 
to  the  anus. 

Q.  Describe  the  pores  or  perforations.  —  A.  There 
are  three.  First,  those  surrounding  the  hair.  Sec- 
ondly, exhalcnt  pores.     Tliii'dly,  absorbent  pores. 

Q.  How  is  the  cutis  designated?  —  A.  As  the  cutis 
vera,  or  true  skin. 

Q.  "VYhat  is  the  structure  of  the  cutis  ?  —  A.  It  is  of 
a  fibrous  texture,  tough,  elastic,  vascular,  and  highly 
eensitive,  and  is  what  we  commonly  denominate  leather. 


Q.  What  are  the  attachments  of  the  cutis?  —  A. 
The  cutis  is  attached  to  the  subjacent  parts  by  cellu- 
lar membrane,  in  some  places  so  tensely  that  httle  or 
no  motion  is  admitted  of;  in  others  so  loosely  that  it 
admits  of  being  tlu'o\ATi  into  folds.  About  the  forehead, 
ujDon  the  back,  around  the  tail,  and  upon  the  pasterns, 
it  can  scarcely  be  pinched  up ;  but  upon  the  sides  of  the 
face  and  neck,  upon  the  ribs,  along  the  flanks,  and  upon 
the  anus  and  thighs,  it  will  easily  admit  of  duplication. 

Q.  What  varieties  are  there  in  the  density  of  the 
cutis  ?  —  A.  It  varies  in  density,  not  only  where  it  covers 
different  parts  in  the  same  animal ;  but  in  horses  of 
different  breeds  and  temperaments,  it  varies  very  essen- 
tially. 

Q.  AVhat  is  the  organization  of  the  rete  mucosimi  ? 
A.  It  is  composed  of  a  fine,  delicate,  laminated  tissue, 
interposed  between  the  cuticle  and  cutis,  and  serves  as 
their  connecting  medium,  and  is  supposed  to  secrete 
the  coloring  matter  of  the  external  surface  and  hair. 

(14) 


ANATOMY  AND  PHYSIOLOGY  OF  THE  HORSE. 


15 


PHYSIOLOGY    OF    THE    SKIN. 

The  skin  is  higlily  sensitive  ;  yet  those 
persons  who  are  in  the  habit  of  making  free 
use  of  the  whip  scarcely  ever  realize  the 
fact.  The  author  has  an  impression  that 
the  skin  of  a  horse  is  more  sensitive  than 
that  of  man ;  for  example,  let  a  small  quan- 
tity of  turpentine  be  applied  to  a  horse's 
back, — very  soon  he  evinces  signs  of  pain, 
which  cannot  be  elicited  when  a  man  be- 
comes the  subject  of  the  same  experiment. 
Every  horse-owner,  also,  must  have  noticed 
the  uneasiness  a  horse  manifests  when  a 
common  fly,  or  gad-fly,  alights  on  him ;  and 
in  a  variety  of  other  ways  the  highly  sensi- 
tive state  of  a  horse's  skin  admits  of  dem- 
onstration. 

The  skin  is  one  of  the  principal  emunc- 
tories  of  the  body,  from  the  surface  of  which 
passes  off  a  large  quantity  of  morbid  fluid 
in  the  form  of  perspiration,  sensible  or  in- 
sensible, as  the  case  may  be.  The  skin  is 
the  great  external  outlet;  and,  should  the 
kidneys  or  any  other  organ  fail  to  play  their 
part  in  eliminating  useless  fluids,  the  skin 
opens  its  flood-gates,  and  thus  purifies  the 
body.  The  amount  of  fluid  exhaled  from 
the  external  surface  has  been  the  subject  of 
some  very  interesting  experiments,  and  the 
results  are  truly  astonishing. 

OF    THE    CELLULAR    MEMBRANE  BENEATH  THE 

SKIN. 

This  tissue  abounds  in  almost  every  part 
of  the  body;  thus,  says  Carpenter,  "it  binds 
together  the  ultimate  fibres  of  the  muscles 
into  minute  fasciculi,  unites  this  fasciculi 
into  larger  ones,  these  again  into  still  larger, 
wMch  are  obvious  to  the  eye,  and  these  into 
the  entire  muscle ;  and  also  forms  the  mem- 
branous divisions  between  distinct  muscles. 
In  like  manner  it  unites  the  elements  of 
nerves,  glands,  etc.,  binds  together  the  fat- 
cells  into  minute  masses,  these  into  larger 
ones,  and  so  on ;  and  in  this  manner  pene- 
trates and  forms  a  considerable  part  of  all 
the  softer  tissues  of  the  body.  It  also  serves 
as  the  bed  in  which  blood-vessels,  nerves, 
and  lymphatics  may  be  carried  into  the 
substance  of  the  different  organs." 


This  tissue  consists  of  a  net-work  of 
minute  fibres  and  bands,  which  are  inter- 
woven in  every  direction,  so  as  to  leave  in- 
numerable areola,  or  spaces,  which  commu- 
nicate freely  with  one  another. 

Of  these  fibres,  some  are  of  the  yellow  or 
elastic  land,  but  the  majority  are  composed 
of  the  white  fibrous  tissue ;  and,  as  in  the 
other  form  of  elementary  structure,  they 
frequently  present  the  form  of  broad  flat- 
tened bands,  or  membranous  shreds,  in 
which  no  distinct  fibrous  arrangement  is 
visible.  The  proportion  of  the  two  forms 
varies,  according  to  the  amount  of  elasticity 
or  simple  resisting  power  which  the  en- 
dowments of  the  part  require.  The  inter- 
stices or  areolae  are  filled,  during  life,  with 
a  fluid  which  resembles  very  dilute  serum 
of  the  blood ;  consisting  chiefly  of  water,  but 
containing  a  sensible  quantity  of  common 
salt  and  albumen.  It  is  the  undue  accumu- 
lation of  this  fluid  wliich  constitutes  drop- 
sical effusion,  the  influence  of  gravity  upon 
the  seat  of  which,  shows  the  free  communi- 
cation that  exists  among  the  interstices. 
This  freedom  of  eommunication  is  still 
more  shown,  however,  by  the  fact,  that 
either  air  or  water  may  be  made  to  pass,  by 
a  moderate  continued  pressure,  into  almost 
every  part  of  the  body  containing  cellular 
or  areolar  tissue,  although  introduced  only 
at  a  single  point.  In  this  manner  it  is  the 
habit  of  butchers  to  inflate  veal;  and* 
impostors  have  thus  blown  up  the  scalps 
and  faces  of  their  children,  in  order  to  ex- 
cite commiseration.  The  whole  body  has 
been  thus  spontaneously  distended  with  air 
by  emphysema  in  the  lungs;  the  air  having 
escaped  from  the  air-cells  into  the  surround- 
ing areolar  tissue,  and  thence,  by  the  con- 
tinuity of  tliis  tissue  with  that  of  the  body 
in  general  at  the  root  or  apex  of  the  lungs, 
into  the  entire  fabric. 

The  structure  of  the  serous  and  synovial 
membranes  is  essentially  the  same  as  the 
above.  The  true  cellular  membrane  is 
sometimes  termed  reticular,  while  that  con- 
taining fat  is  called  adipose . 


16 


ANATOMY    AND    PHYSIOLOGY   OF 


ADIPOSE    OR    FATTY    TISSUE. 

The  adipose  tissue  is  composed  of  iso- 
lated cells,  which  appropriate  fatty  matter 
from  the  blood  after  the  same  manner  as 
the  secreting  cells  appropriate  the  elements 
of  bile,  urine,  and  milk.  "  The  portion  of 
fatty  matter  separated  from  the  circulating 
fluid  to  form  adipose  tissue,  is  only  that 
which  can  be  spared  from  the  other  pur- 
poses to  which  they  have  to  be  applied ;  and 
hence  the  production  of  this  tissue  depends, 
in  part,  upon  the  amount  of  fatty  matter 
taken  in  as  food.*     This  is  not  entirely  the 

*  "Deposition. — In  almost  all  animals  that  arc  healthy, 
copious  food  of  a  nutritive  kind,  combined  with  little  labor, 
■will  increase  the  deposition  of  fat ;  but  in  the  human  sub- 
ject, and,  indeed  in  many  quadrupeds,  the  animal  spirits 
appear  to  have  very  considerable  influence  over  this  secre- 
tion. We  see  numberless  examples  of  people,  wlio  appear 
to  enjoy  the  best  bodily  health,  and  yet  arc  constantly 
meagre,  though  their  food  and  habits  of  life  tend  to  an  op- 
posite state ;  and  we  may  occasionally  observe  horses  and 
dogs,  particularly  circumstanced,  in  which,  from  their 
natural  leanness,  or  poorness  upon  the  rib,  something  of 
a  mental  nature  would  appear  to  be  operating ;  indeed,  it 
is  a  well  known  truth,  that  if  you  separate  a  horse  of  an 
irritable  disposition  from  others  with  whom  he  is  accus- 
tomed to  be  stalled,  he  will  fall  away  in  condition,  in  con- 
sequence of  (to  use  the  vulgar  expression)  fretting  from 
being  alone;  and  so  much  does  tliis  act  of  segregation  affect 
some,  that  I  have  known  them  even  refuse  their  food. 
Those  horses  are  commonly  the  fattest  that  ai"e  fed  on 
easily  digestible  food — such  as  bruised  or  scalded  corn, 
roots  of  a  nutritive  kind,  chopped  hay,  etc.,  and  that 
have  little  or  no  exercise  :  a  fact  well  appreciated  by  the 
horse-dealer,  whose  horses  arc  fine  and  ft  for  sale,  but  in- 
capable of  fatigue. 

Absorption.  —  Constitutional  diseases,  generally  speak- 
ing, extenuate  the  body,  and  more  particularly  such  as  are 
of  the  acute  or  painful  description ;  hence,  the  irritation 
caused  by  a  simple  puncture  in  the  foot,  will,  if  it  be  of 
long  duration,  induce  a  state  of  emaciation  :  under  which 
circumstances,  the  absorbents  are  supposed  to  act  with  more 
than  ordinary  eff"ect,  and  to  take  up  the  adeps  from  the 
interior  of  its  cells  — Percivall. 


case,  however,  as  some  have  maintained ; 
for  there  is  sufficient  evidence  that  animals 
may  produce  fatty  matter  by  a  process  of 
chemical  transformation,  from  the  starch  or 
sugar  of  their  food,  when  there  is  an  unusual 
deficiency  of  it  in  the  aliment."  Liebig 
wrrites :  "  Whatever  views  we  may  entertain 
regarding  the  origin  of  the  fatty  constitu- 
ents of  the  body,  this  much,  at  least,  is  un- 
deniable, that  the  herbs  and  roots  consumed 
by  the  cow  contain  no  butter ;  that,  in  the 
hay  or  other  fodder  of  oxen,  no  beef-suet 
exists ;  that  no  hog's-lard  can  be  found  in 
the  potato  refuse  given  to  swine ;  and  that 
the  food  of  geese  or  fowls  contains  no 
goose  nor  capon  fat.  The  masses  of  fat 
found  in  the  bodies  of  these  animals  are 
formed  in  their  organism ;  and,  when  the 
full  value  of  this  fact  is  recognized,it  entitles 
us  to  conclude,  that  a  certain  quantity  of 
oxygen,  in  some  form  or  other,  separates 
from  the  constituents  of  their  food,  for 
without  such  a  separation  of  oxygen,  no 
fat  could  possibly  be  formed  from  any  one 
of  these  substances." 

The  chemical  analysis  of  the  constituents 
of  the  food  of  the  graminivora  shows  in 
the  clearest  manner  that  they  contain  carbon 
and  oxygen  in  certain  proportions;  which, 
when  reduced  to  equivalents,  yield  the  fol- 
lowing series : 

"  In  vegetable  fibrine,  albumen,  and  cas- 
eine,  there  are  contained,  for  — 

120  eq.  carbon,      3G  eq.  oxygen. 
In  starch,  120   "        "  100  " 

«  cane  sugai",      120   "         "  110  " 

«  gum,  120   "         "  110  "  " 

"  sugar  of  milk,  120   "         "  120  "  " 

"  grape  sugar,    120   "         "  140  "  •' 


EXAMINATIONS  RESUMED. 


CELLUL/Ul  MEMBK.VXE. 

Q.  What  is  the  principal  use  of  cellular  membrane  ? 

—  A.  It  is  employed  in  uniting,  covering,  and  defending 
various  parts  of  the  body. 

Q.  Does  cellular  differ  from  serous  or  nervous  mem- 
branes ?  —  A.  No,  they  are  all  resolvable  into  the  same 
constituents. 

Q.  How  does  the  periosteum  differ  from  the  above  ? 

—  A.  It  presents  itself  in  a  more  condensed  form. 


Q.  IIow  do  capsules  of  joints  differ  from  common 
cellular  membrane?  —  A.  They  ai'e  a  modification  of 
it,  under  a  condensed  form. 

Q.  In  what  part  of  the  animal  does  cellular  mem- 
brane exist  in  greatest  abundance  ?  —  A.  Immediately 
beneath  the  skin  ;  upon  the  ribs,  and  about  the  breast, 
and  under  the  jaws,  m  the  scrotum,  on  the  inside  of 
the  elbow  and  tliigh. 


THE   HORSE. 


IT 


"  Now  in  all  fatty  bodies  there  are  con- 
tained, on  an  average : 

"  For  120  eq.  carbon,  only  10  eq.  oxygen. 

"  Since  the  carbon  of  the  fatty  constit- 
uents of  the  animal  body  is  derived  from 
the  food,  seeing  that  there  is  no  other 
source  from  whence  it  can  be  derived,  it  is 
obvious,  if  we  suppose  fat  to  be  formed 
from  albumen,  fibrine,  or  casein,  that  for 
every  120  equivalents  of  carbon  deposited 
as  fat,  26  equivalents  of  oxygen  must  be 
separated  from  the  elements  of  these  sub- 
stances ;  and,  further,  if  we  conceive  fat  to 
be  formed  firom  starch,  sugar,  or  sugar  of 
milk,  that  for  the  same  amount  of  carbon 
there  must  be  separated  90,  100,  and  110 
equivalents  of  oxygen  from  these  com- 
pounds respectively. 

"  There  is  therefore  but  one  way  in  which 
the  formation  of  fat  in  the  animal  body  is 
possible,  and  this  is  absolutely  the  same  in 
which  its  formation  in  plants  takes  place ; 


it  is  a  separation  of  oxygen  from  the  ele- 
ments of  food." 

OF   THE   EXTERNAL   PARTS. 

THE    HOOF.* 

"  The  hoof  is  the  horny  case  or  covering 
nature  has  provided  for  the  protection  of 
the  sensitive  parts  of  the  foot.  It  may  be 
said  of  itself  to  constitute  such  a  shoe  or 
defence,  as  enables  the  animal  in  his  wild 
state  to  travel  about  in  quest  of  food,  not 
only  without  injury  to  the  structures  under- 
neath it,  but  with  a  degree  of  elasticity  that 
preserves  his  whole  frame  from  concussion. 
Were  one  forced  into  any  comparison  of 
the  sort,  it  must  be  admitted  that  the  hoofs 
of  animals  bear  some  anatomical  affinity 
to  the  human  nails,  or  claws,  of  other 
animals ;  though  they  are  vastly  superior 
in  physiological  importance  to  any  such 
appendages  as  these. 

*  Percivall's  Anatomy. 


EXAMINATIONS  RESUMED. 


ADIPOSE   TISSUE. 

Q.  What  IS  the  fatty  matter  contained  in  the  adiijose 
cells  composed  of?  —  A.  Steariue,  margarine,  and 
oleine. 

Q.  How  do  they  appear  when  isolated?  —  A.  The 
two  former  are  solid,  and  the  latter  is  fluid. 

Q.  How  are  they  preserved  in  a  fluid  state  in  the 
animal  body  ?  —  A.  By  the  ordinary^  temperature  of 
the  body. 

Q.  What  are  the  observable  differences  in  color 
occurring  in  different  jiarts  of  the  body,  and  in  animals 
of  diverse  temperaments  ?  —  A.  In  some  parts  of  the 
body  it  is  white,  in  others  it  has  a  yellow  tinge ;  in 
animals  of  lymphatic  and  nervous  temperaments  it  is 
wliite;  in  the  sanguine  it  has  somewhat  of  a  red 
tinge ;  in  the  bilious,  it  presents  a  yellow  appearance. 

Q.  The  fat  at  the  ordinary  temperatm-e  of  the  li\-ing 
body  being  fluid,  how  is  it  retained  m  the  fat  cells  with- 
out transudation  ? —  A.  The  intervals  of  the  fat  cells 
are  traversed  by  a  minute  net-work  of  blood  A'essels, 
from  which  they  derive  their  secretion ;  and  it  is  prob- 
ably by  the  constant  moistening  of  their  walls  with  a 
watery  fluid,  that  their  contents  are  retained. 

Q.  What  are  uses  of  the  adipose  tissue? — A.  It  is 
intended  to  fill  up  spaces ;  forms  a  sort  of  cusliion  or 
pad  for  the  support  of  movable  parts.  It  also  acts  as 
a  non-conductor  of  heat,  thus  preser\ing  the  animal 
temperature;  it  serves  as  a  reservoir  of  combustible 
3 


matter,  at  the  expense  of  which  the  respiration  may  be 
maintained  when  other  materials  are  deficient. 
i  Q.  Suppose  you  desired  to  fatten  a  horse  or  an  ox, 
what  method  should  you  adopt  ?  *  —  A.  I  should  keep 
the  animal  at  rest,  and  furnish  him  with  an  abundance 
of  nitrogenized  food. 

Q.  In  what  vegetable  constituents  does  nitrogen 
abound  ?  —  A.  In  vegetable  fibrine,  albumen,  and 
caseine. 

*  Experience  teaches  us  that,  in  poiiltry,  the  maximum  of  fat  is 
obtained  by  tying  the  feet,  and  by  a  medium  temperature.  These 
animals  in  such  circumstances  may  be  compared  to  a  plant  possessing 
in  the  highest  degree  the  power  of  converting  all  the  food  into  parts  of 
its  own  structure.  The  excess  of  the  constituents  of  blood  forms 
flesh  and  other  organized  tissues,  while  that  of  starch,  sugar,  etc.,  is 
converted  into  fat.  When  animals  are  fattened  on  food  destitute  of 
nitrogen,  only  certain  parts  of  their  structure  increase  in  size.  Thus, 
in  a  goose,  fattened  in  the  method  above  alluded  to,  the  liver  becomes 
three  or  four  times  larger  than  in  the  same  animal,  when  well  fed 
with  free  motion,  while  we  cannot  say  that  the  organized  structure 
of  the  liver  is  thereby  increased.  The  Uver  of  a  goose  fed  in  the 
ordinary  way  is  firm  and  elastic ;  that  of  the  imprisoned  animal  is 
soft  and  spongy.  The  difference  consists  in  a  greater  or  less  expan- 
sion of  its  cells  which  are  filled  with  fat. 

In  some  diseases,  the  starch,  sugar,  etc.,  of  the  food  obviously  do  not 
undergo  the  changes  which  enable  them  to  assist  in  respiration,  and 
consequently  to  be  converted  into  fat.  Thus,  in  diabetes  melUtua, 
the  starch  is  only  converted  into  grape  sugar,  which  is  expelled 
from  the  body  without  further  change. 

In  other  diseases,  as  for  example  in  inflammation  of  the  liver,  we 
find  the  blood  loaded  with  fat  and  oil ;  and  in  the  composition  of  the 
bile  there  is  nothing  at  all  inconsistent  with  the  supposition  that 
some  of  its  constituents  may  be  transformed  into  fat. 


18 


ANATOMY   AND   PHYSIOLOGY   OF 


"  Form.  —  Sainbel  viewed  the  foot  as 
'  the  segment  of  an  oval,  opened  at  the 
back,  and  nearly  round  in  front.'  To  a 
common  observer,  the  hoof  exhibits  a  conoid 
form  ;  tlie  part  resting  upon  the  ground 
being  the  basis,  the  vacuity  above,  the  ob- 
truncated apex.  IVIr.  Bracy  Clark  asserts 
that  this  view  is  incorrect,  and  that  the 
general  figure  of  the  hoof  is  a  cylinder^ 
very  obliquely  trmicated  upon  its  ground 
surface.  This  he  demonstrates  in  two 
ways ;  either  by  rolling  up  a  piece  of  paper 
into  the  shape  of  a  cylinder,  and  afterwards 
cutting  one  of  its  ends  in  a  very  slanting 
direction ;  or  by  taking  a  carpenter's  square, 
and  placing  one  limb  beneath  the  foot 
across  the  quarters,  then  sloping  the  other 
backward  against  the  side  of  the  quarters, 
parallel  to  the  front,  when  the  edge  of  the 
iron  will  be  found  parallel  to  the  wall  of 
the  hoof.  This  corrected  view  of  its  figure 
will  serve  to  account  for  the  general  equi- 
formity  manifest  in  the  hoof,  and  also  for 
the  undeviating  correspondence  found  to 
exist  between  its  slope  or  slant,  as  well  in 
front  as  behind,  which  in  an  ordinary  or 
healthy  foot  may  be  estimated  at  an  angle 
of  45*^.  Around  the  coronet,  where  the 
hoof  unites  with  the  skin,  the  cylinder  is 
cut  directly  across  its  perpendicuJar  —  at 
right  angles  with  it :  it  is  the  oblique  trun- 
cation of  its  ground-surface  that  occasions 
the  slant,  which  latter  we  may  consequently 
increase  at  pleasure  by  any  means  that 
augment  the  former,  viz. :  by  lowering  the 
heels ;  by  cutting  away  a  prominent  frog ; 
or  by  putting  on  thin-heeled  shoes.  At  the 
same  time  that  we  increase  the  slant  of  the 
hoof,  we  increase  the  obliquity  of  the  pas- 
terns, and  likewise  proportionately  augment 
the  ground-surface  of  the  hoof,  from  heel  to 
toe,  the  breadth  remaining  unaltered ;  and 
in  the  same  ratio,  consequently,  extend  the 
surface  of  tread.* 

"  Spread.  —  By  the  spread,  is  meant  the 
inclination  the  hoof  manifests,  when  left 
unshod,  around  the  toe  and  sides,  to  bulge 

*  For  further  elucidation  on  the  cylindrical  form  of  the 
foot,  consult  Rlr.  Bracy  Clark's  works  on  the  Foot  of  the 
Horse. 


or  protrude  at  bottom,  whereby  its  ground- 
surface  becomes  augmented,  particularly 
around  the  outer  quarter.  To  a  certain  ex- 
tent this  is  worthy  of  observation ;  although, 
in  my  opinion,  it  is  to  be  regarded  rather  as 
an  effect  of  pressure  than  one  of  abstract 
growth.  The  surface  of  inclination  upon 
which  the  horn  is  produced  has  no  such 
spread,  nor  can  the  hoof  itself  be  said,  from 
growth  alone,  to  have  any  such  natural  ten- 
dency; but,  as  it  continues  to  grow  and 
shoot  beyond  the  inner  foot  that  produced 
it,  and  to  which  it  was  so  intimately  united, 
it  yields  to  the  pressure  of  the  animal's 
weight,  and  bulges  or  spreads  out,  and 
more  at  the  outer  side  than  the  inner,  in 
consequence  of  the  pressure  tending  more 
in  that  direction.  If  we  examine  a  num- 
ber of  hoofs  of  neglected  growth,  and  con- 
sequent exuberance  and  deformity,  of  va- 
rious descriptions,  we  may  discover  that, 
in  them  all,  the  spread  seems  to  have  been 
the  first  or  incipient  deviation  from  that  line 
of  growth  viewed  as  consistent  with  the 
health  and  well-doing  of  the  foot.  It  is 
only  in  the  unshod  hoof  that  any  spread  is 
found  :  as  soon  as  the  ground-surface  comes 
to  be  confined  by  a  shoe,  pressure  can  no 
longer  exert  its  influence  to  produce  such 
consequences. 

"  Mr.  Goodwin  aptly  observes,  that  '  to 
take  the  form  of  the  hoof  correctly,  we  must 
strip  it  of  its  exuberant  or  superfluous 
parts,  the  same  as  one  would  pare  the  su- 
perabundant growth  off"  our  own  nails. 
The  neglect  of  this  necessary  preparative 
has  led  to  a  considerable  difference  of 
opinion  about  the  natural,  healthy,  or  true 
form  of  the  ground-surface  of  the  foot. 
JVIr.  Bracy  Clark,  I  conceive,  has  inclined 
to  the  side  of  error  in  this  particular ; 
though,  in  the  substitution  of  the  cylin- 
drical for  the  conical  figure  of  the  entire 
hoof,  he  has  certainly  the  advantage  of 
other  wnriters.  His  natural  foot  is  one 
with  great  spread  to  it,  much  of  which 
the  smith  would  find  it  necessary  to  de- 
prive it  of,  even  on  the  first  shoeing ;  and 
the  protuberance  of  the  outer  quarter 
(which   Mr.  C.  points  out  as  an  attribute 


THE   HORSE. 


19 


of  health)  iDeing  wholly  owing-  to  the  spread, 
will,  of  course,  disappear  with  the  annihi- 
lation of  the  spread.'  * 

"  Although  Mr.  Goodwin  has  not  here 
explained  what  he  conceives  to  be  the 
origin  or  cause  of  the  spread,  it  is  evident 
we  both  concur  in  viewing  it  rather  as  a 
deviation  from  health  or  nature  than  a  cir- 
cumstance worthy  of  the  consideration  it 
has  been  accounted  of  by  Mr.  Clark. 

"  Color.  —  Hoofs  are  black  or  white,  or 
some  intermediate  shade,  or  they  may  ex- 
hibit a  black  and  white  striped  or  marbly 
aspect.  It  is  an  old  observation,  and  one 
that  passes  current  among  us  at  the  present 
day,  that  black  or  dark-shaded  hoofs  pos- 
sess greater  strength  and  durability,  and 
indicate  less  proneness  in  the  feet  to  dis- 
ease, than  such  as  are  composed  of  white 
or  striped  horn.  The  rationale  of  which 
appears  to  be,  that  white  horn  (the  same  as 
white  hair)  is  the  product  of  parts  weaker 
by  nature  than  such  as  produce  dark  or 
black  horn,  and,  being  weaker,  consequently 
are  more  liable  to  disease,  less  able  to  resist 
those  impressions  that  tend  to  disorder. 
White  hoofs  are  more  porous  than  black 
ones,  and  consequently  absorb  moisture  and 
lose  it  again  by  evaporation  with  more  fa- 
cility: a  fact  that  may  probably  aid  us  in 
accounting  for  the  failures  attributed  to 
them. 

"Magnitude.  —  It  requires  no  veterinary 
skill  to  discover  any  very  material  dispro- 
portion in  the  magnitude  of  the  foot :  it 
will  strike  us  at  once  as  being  large  or 
small,  in  comparison  to  the  limb  or  the  size 
of  the  animal.  A  foot  of  any  description 
that  is  out  of  proportion  is  to  the  horse 
possessing  it  more  or  less  objectionable : 
but,  for  all  that,  these  out-of-proportion  feet, 
abstractedly  considered,  have  their  advan- 
tages as  weU  as  their  disadvantages.  Sain- 
bel  tells  us,  that  a  large  wide  hoof,  by  ex- 
tending the  surface  of  tread,  '  will  increase 
the  stability  and  j&rmness  of  the  fabric;' 
but  then,  he  adds,  '  this  partial  advantage 
grows  into  an  evil  when  it  becomes  applied 

*  Goodwin's  New  System  of  Shoeing,  edit,  second, 
page  33. 


to  a  body  capable  of  translation,  and  con- 
sidered in  a  state  of  actual  motion ;  be- 
cause, then,  the  mass  and  weight  of  the 
foot  overburthen  the  muscles  of  the  ex- 
tremity.' And  because,  I  would  add,  the 
surfaces  of  contact  being  greater,  the  attrac- 
tion of  cohesion  becomes  greater,  and  so 
much  the  more  muscular  force  is  required 
to  raise  the  foot  (particularly  in  moist 
ground)  from  the  earth.  Besides  which,  a 
large  foot  is  apt  to  become  objectionable 
from  its  striking,  during  action,  the  opposite 
leg.  On  the  other  hand,  it  is  contended, 
that  a  large  foot  will  not  sink  so  deep  into 
soft  ground  as  a  small  one,  and  conse- 
quently will  not  demand  so  great  an  effort 
of  strength  to  draw  it  out.  This  is  an 
argument,  however,  that  can  only  hold  good 
under  the  supposition,  that  in  both  cases 
the  muscular  strength  is  equal,  which  we 
know  but  rarely  to  happen, — in  general, 
broad  or  flat-footed  horses  possessing  supe- 
rior strength  ;  small,  narrow-footed  ones, 
superior  speed.  There  cannot  be  a  doubt 
about  a  large  foot  being  unfavorable  for 
speed,  a  small  one  for  stability;  neither 
one  nor  the  other  can  be  indiscriminately 
found  fault  with  ;  both  within  certain  limits 
possess  their  respective  advantages ;  though 
to  turn  out  as  such,  they  each  of  them  re- 
quire to  be  combined  with  suitable  confor- 
mation and  action. 

"  Large  bulky  hoofs  are  found  to  be 
mechanically  weaker  than  others,  in  conse- 
quence of  being  composed  of  a  thin,  soft, 
porous  description  of  horn.  Sainbel  ascribes 
all  this  to  '  a  relaxation  of  the  fibres  com- 
posing the  hoof:  in  which  case,  the  diame- 
ters of  the  vessels  are  increased,  the  porosi- 
ties are  multiplied,  and  the  fluids  abound 
in  them  in  too  great  quantities ;  conse- 
quently this  kind  of  foot  is  soft,  tender,  and 
sensible.'  Small  feet,  on  the  contrary,  in 
general  possess  a  close -woven  horn,  thick 
in  substance,  and  consequently  prove  strong: 
they  are  rather  oval  than  circular  in  figure, 
with  great  depth  of  substance,  and  are 
found  to  be  of  a  durable  nature.  '  In  feet 
of  this  description,'  says  Sainbel, '  from  the 
too  close  union  and  too  close  tension  of 


20 


ANATOMY   AND   PHYSIOLOGY   OF 


their  fibres,  the  vessels  destined  to  conduct 
the  nutritious  fluid  are  contracted  and 
obliterated  ;  whence  proceeds  that  dryness 
of  the  part  which  renders  the  horn  brittle 
and  liable  to  split.'  * 

"  Division.  —  To  the  common  observer 
the  hoof  appears  to  consist  of  one  entire 
or  indivisible  case  ;  but  the  anatomist  finds, 
by  subjecting  it  to  maceration,  or  coction, 
or  even  to  putrefaction,  that  it  resolves 
itself  into  three  separate  pieces  :  still,  so 
long  as  the  hoof  maintains  its  integrity, 
such  is  the  force  of  cohesion  existing  be- 
tween these  three  parts,  that  we  as  easily 
rend  it  in  any  other  place  as  dissever  one 
of  its  jointures.  These  constituent  parts 
are  the  wall^  the  sole,  and  i\\efrog. 

THE    WALL. 

"  The  wall  or  crust  is  the  part  of  the 
hoof  which  is  visible  while  the  foot  stands 
upon  the  ground.  It  forms  a  circular 
boundary  wall  or  fence  inclosing  the  inter- 
nal structures.  On  taking  up  the  foot,  we 
find  the  wall  prominent  all  round  beyond 
the  other  parts,  making  the  first  impression 
upon  the  ground,  and  evidently  taking  the 
largest  share  of  bearing.  It  is  the  part  to 
which  the  shoe  is  nailed.  It  is,  in  fact,  the 
most  important  division  of  the  hoof;  ap- 
pearing to  form  (in  the  words  of  IVIr.  Clark) 
'the  basis  or  first  principle  in  the  mechan- 
ism of  the  hoof,  the  other  parts  being  all 
subordinate  to  this.' 

"  Situations  and  Relations.  —  The  wall 
takes  its  beginning  at  the  coronet,  from  the 
terminating  circular  border  of  the  skin, 
with  which  it  is  intimately  united ;  their 
line  of  union  being  concealed  by  a  row  of 
overhanging  hairs.  From  the  coronet  the 
wall  descends  in  an  oblique  direction  to 
the  bottom  of  the  foot,  where  it  em- 
braces the  sole,  and  terminates  in  a  cir- 
cular projecting  border.  The  anterior  and 
lateral  parts  of  the  hoof  are  formed  entirely 
by  the  wall ;  but  at  the  posterior  part,  in- 
stead of  the  heels  of  the  wall  being  con- 
tinued one  into  the  other  so  as  to  complete 
the  circle,  they  become  inflected,  first  down- 

*  Sainbel's  Lectures  on  the  Elements  of  Farriery. 


ward,  afterwards  forward  and  inward,  and 
are  elongated  in  the  latter  direction  until 
they  reach  the  centre  of  the  bottom  of  the 
foot,  where  they  terminate :  these  inflec- 
tions or  processes  of  the  wall  constitute  the 
bars.  Altogether,  the  wall  may  be  said  to 
form  about  two-thirds  of  the  entire  hoof. 

"  Connection.  —  Superiorly,  around  the 
coronet,  the  wall  is  united  with  the  skin ; 
inferiorly,  within  its  circumferent  border, 
with  the  sole  ;  posteriorly,  between  its  heels, 
with  the  heels  of  the  frog;  inferiorly,  be- 
tween the  bars,  with  the  sides  of  the  frog ; 
and  internally,  with  the  sensitive  laminae. 
Let  us  now  consider  the  wall  in  its  detached 
or  separate  state. 

"  Figure.  —  That  of  a  hollow  cylinder, 
having  the  sides  presented  to  the  ground  cut 
much  aslant,  and  whose  circle  exhibits  a 
hiatus  or  deficiency  behind,  from  the  lateral 
boundaries  of  which  issue  tvvo  narrow  pro- 
cesses or  appendages.  Taking  a  lateral 
view,  the  wall  assumes  a  conical  shape, 
being  broad  and  deep  in  fi'ont,  and  gradually 
narrowing  as  it  stretches  backward. 

^^ Division.  —  For  facility  of  reference,  and 
in  aid  of  our  descriptions,  we  distinguish 
in  the  wall.  First,  the  toe;  secondly,  the 
quarters;  thirdly,  the  heels;  fourthly,  the 
superior  or  coronary  border ;  fifthly,  the  in- 
ferior or  solar  border ;  sixthly,  the  lamince 
or  lamellae;  lastly,  the  bars  or  appendages. 

"  The  Toe  forms  the  bow  or  front  of  the 
hoof,  and  comprehends  about  two-thirds  of 
the  superfices  of  the  wall.  It  is  the  deep- 
est, broadest,  and  thickest  part  of  the  wall ; 
for  reasons  that  will  appear  hereafter.  It 
exhibits  a  degree  of  slant  about  equal,  nat- 
vnally,  to  an  angle  of  forty-five  degrees; 
though  there  are  variations  from  this  which 
(as  was  explained  before)  will  be  found,  in 
a  measure,  to  be  dependent  upon  the  oblique 
truncation  of  the  cylinder.  When  we  come 
to  understand  the  physiology  of  this  part, 
however,  a  more  operative  and  efficient 
cause  for  this  variation  will  be  found  in  the 
weight  the  wall  has  to  sustain,  and  in  its 
own  mechanical  strength  or  force  of  resist- 
ance :  on  which  principle  it  is  that  light 
horses,  thorough-breds,  and  ponies,  as  well 


EXPLANATION   OF   FIGURE   III. 


MUSCULAR  STRUCTURE. 

a".  Trapezius. 

6.  Rhomboideus  longus. 

c".   Scalenus;  and  tT.  Splenius. 

e".  Pectoralis  parvus. 

f".  Antea  spinatus. 

g".  Postea  spinatus. 

a  and  D.  Serratus  magnus. 

6'.    Intercostales. 

c'.    Obliquus  extern  us  abdominis. 

d\  Obliquus  internus  abdominis. 

e\    Erector  coccygis. 

f\  Depressor  coccygis. 

<7';    Compressor  coccygis. 

7j'.  i\  Gluteii  muscles.     Jk  Triceps  abductors. 

K.    Biceps  abductor  femoris. 

m'.  Tensor  vaginae. 

n\    Rectus. 

o'.    Vastus  externus. 

r'.  s'.  Gastrocnemius  externus,  and  plantaris. 

«'.   Flexor  pedis  accessorius ;  its  fleshy  belly. 

y\   Peroneus. 

x\   Extensor  pedis. 

Zt".  Teres  major. 

i".   Latissimus  dorsi. 

J.    Pectoralis  magnus. 

K.  Humero  cubital.     (Pectoral  region.) 

Z".    Scapido-ulnaris. 

m".  n".  Triceps  extensor  brachii. 

o".  Pectoralis  transversalis. 

p".  Flexor  metacariDi,  externus. 

u.  V.  Levator  humeri,  and  Sterno  masillaris. 

s".    Extensor  metacarpi  magnus. 

x".  Extensor  pedis. 

At  the  inferior  part  of  the  abdomen  the  letter  Ti.  occurs;   it  should  be  4.  4 

The  subcutaneous  thoracic  vein  Ti.y  however,  serves  to  indicate  the  region  of 

the  rectus  abdominalis. 

7.  The  sheath. 

*.     Ligamentum  colli. 


THE   HOESE. 


21 


belonging  to  the  inner  part,  which  is  the 
beginning  of  the  wall  itself;  the  external 
edge  to  the  white  band  by  which  the  other 
is  embraced,  and  to  which  Mr.  Clark  has  in 
particular  drawn  our  attention,  under  the 
appellation  of  Coronary  Frog-band.  This 
covers  the  proper  or  veritable  coronary  bor- 
der of  the  hoof;  having,  through  its  fibres, 
which  are  very  fine,  a  sort  of  dove-tailed 
connection  with  it.  As  it  recedes  backward, 
it  grows  broader  to  that  degree,  that  its 
breadth  at  length  becomes  doubled ;  being 
about  half  an  inch  broad  in  front,  and  one 
inch  behind.  It  is  thickest  around  its  mid- 
dle parts  ;  its  inferior  edge,  like  the  superior, 
becoming  attenuated,  until  it  grows  so  fine 
as  to  end  in  imperceptible  union  with  the 
substance  of  the  wall,  giving  it  its  beauti- 
fully polished  surface :  from  the  heat,  how- 
ever, to  which  the  hoof  is  artificially  exposed, 
the  thin  part  below  the  coronet  often  grows 
arid,  splits  from  the  crust,  and  becomes 
everted ;  turning,  at  the  same  time,  in  con- 
sequence of  dryness,  of  a  whitish  complex- 
ion. Posteriorly,  we  find  it  continued  round 
the  heels  of  the  wall  and  frog,  and  from 
thence  across  the  back  of  the  cleft,  forming 
altogether  a  complete  circle,  and  everywhere 
showing  itself  to  be  the  medium  of  connec- 
tion between  the  skin  and  the  hoof  It  has 
been  already  stated  that  the  cutis  terminates 
in  a  circular  border,  let  into  a  groove  around 
the  summit  of  the  wall :  the  cuticle,  how- 
ever, does  not  end  here  —  it  is  continued 
down ;  in  fact,  we  trace  it  to  the  horny 
band  we  have  been  describing,  the  one  being 
continuous  in  substance  with  the  other.  In- 
deed, the  only  detectible  differences  in  them 
are,  that  one  is  thicker  than  the  other,  and 
grows  hard,  and  dry,  and  white,  from  the 
effects  of  heat  upon  it  from  without,  and 
the  want  of  moisture  from  within.  This 
cuticular  origin  and  assimilation  may  be 
demonstrated  in  the  putrefied  foot ;  or,  bet- 
ter still,  in  the  foot  of  the  foetus.  The  band 
is  broader  at  the  heels  than  elsewhere,  in  con- 
sequence of  the  greater  breadth  of  exposed 
cutis  at  those  parts.  In  its  texture  it  is 
fibrous,  and  its  fibres  pursue  the  same  direc- 
■^^ion  as  those  of  the  wall,  from  which  they 


differ  only  in  being  of  a  finer  texture.  Mr. 
Bracy  Clark  appears  to  entertain  some  sin- 
gular notions  in  regard  to  the  structure,  but 
more  particularly  the  uses,  of  this  part; 
which,  in  the  respect  I  bear  for  their  author, 
I  shall  consider,  when  the  time  may  arrive 
for  me  to  treat  of  the  physiology  of  the 
foot. 

"  The  Inferior  or  Solar  Border  offers  but 
little  worthy  of  observation.  It  constitutes 
the  ground  or  wearing  surface  of  the  wall, 
and  is  the  part  to  which  we  nail  the  shoe. 
It  grows  thicker  and  more  exuberant  around 
the  toe  than  in  other  places,  and,  from  its  pro- 
jecting beyond  the  sole,  presents  a  conven- 
ient and  suitable  hold  for  the  nails  of  the 
shoe.  Around  the  anterior  and  lateral  parts, 
it  embraces  the  sole ;  behind,  it  joins  the 
bars,  which  two  points  of  union  form  two 
principal  bearing  places  for  the  shoe.  The 
inferior  border  possesses  a  larger  circumfer- 
ence than  the  superior,  in  consequence  of 
the  oblique  detruncation  of  the  hoof. 

"  This  is  a  part  that  requires  paring  down 
every  time  the  horse  is  shod.  Such  is  its 
exuberating  nature,  that  (lilie  the  human 
nail),  were  it  not  continually  kept  worn 
down,  or  broken,  or  cut  off,  it  would  elon- 
gate very  considerably,  and  gradually  turn 
up,  exhibiting  forms  not  only  of  the  most 
unsightly  but  even  grotesque  description, 
and  proving  incommodious  to  a, degree  to 
be  almost  entirely  destructive  of  progres- 
sion. 

"  The  LamincB  (better  named  lamellce) 
consist  of  numerous  narrow  thin  plates  or 
processes,  arranged  with  the  nicest  order 
and  mathematical  precision  upon  the  inter- 
nal surface  of  the  wall.  They  extend,  in 
uniform  parallels,  in  a  perpendicular  direc- 
tion from  the  lower  edge  of  the  superior 
border  down  to  the  line  of  junction  of  the 
wall  with  the  sole ;  and  are  so  thickly  set 
that  no  part  of  the  superfices  remains  un- 
occupied by  them.  They  are  likewise  con- 
tinued upon  the  surfaces  of  the  bars.  In 
the  recent  subject  they  are  found  soft,  yield- 
ing, and  elastic ;  but  from  exposure  they 
become  dry  and  rigid. 

"  Every  lameUae  exhibits  two  edges  and 


22 


ANATOMY   AND   rHYSIOLOGY   OP 


as  mules  and  asses,  have  vpright  or  strong^ 
feel  (i.  c),  walls  but  moderately  sloped; 
wiiercas  heavy  horses,  cart-horses,  and 
coach-horses,  have  commonly  Jlat  or  weak 
feet  (i.  e.),  walls  that  slant  immoderately. 
And  (as  was  before  observed)  upon  the 
degree  of  obliquity  of  the  wall  must  very 
much  depend  that  of  the  pasterns.  In  esti- 
mating the  slant  or  slope  of  the  wall,  it  is 
proper  to  distinguish  between  that  which  is 
consequent  on  the  detruncation  of  the  hoof, 
and  such  as  is  the  effect  of  a  burthen  under 
which  the  wall  succumbs.  The  depth  of 
horn  in  front  of  the  toe,  measuring  from  the 
termination  of  the  skin  to  the  most  promi- 
nent point  below  (and  supposing  the  hoof 
to  be  cut  and  ready  to  receive  the  shoe), 
may  be  rated  at  about  three  and  a  half 
inches.  The  bow  or  degree  of  convexity 
of  the  toe  in  front  must  depend  upon  its 
obliquity  as  well  as  upon  the  circularity  of 
the  foot.  The  thickness  of  the  horn  com- 
posing the  toe  may  be  estimated  at  three- 
eighths  of  an  inch,  or  from  that  to  half  an 
inch,  and  this  substance  is  the  same  from 
immediately  beneath  the  coronary  circle  to 
the  junction  of  the  wall  with  the  sole ;  at 
which  part  there  is  an  accession  of  horny 
matter  to  block  up  the  interstices  bet\veen 
the  laminae,  and  also  to  fill  the  angular 
vacuity  that  would  otherwise  exist  here 
between  the  wall  and  sole.  In  the  fore-feet, 
the  toe  is  thicker  in  substance  than  either 
the  quarters  or  heels ;  but  (we  have  it  from 
Sainbel)  '  in  the  hind,  on  the  contrary,  the 
heels  and  quarters  are  generally  thicker  than 
the  toe.' 

"  The  Quarters  are  the  portions  of  the 
wall  intermediate  between  the  toe  and  the 
heels.  They  are  commonly  described  as 
standing  upright^  and,  according  to  a  car- 
penter's square  set  against  the  wall,  so  they 
appear  to  do ;  this  is  not,  however,  the  view 
the  anatomist  ought  to  take  of  their  posi- 
tion :  to  him  the  oblique  course  of  their 
component  fibres,  together  with  the  slant  of 
their  lamina?,  demonstrate  that  they  slope 
in  the  same  manner  and  degree  as  the  toe 
does.  The  quarters  do  not  run  in  straight 
lines  from  before  backward,  but  by  their 


prominence  describe  gentle  curves,  the  outer 
making  a  wider  sweep  than  the  inner. 
This  gives  the  hoof  altogether  a  sort  of 
livisted  appearance,  and  makes  the  inner 
part  of  the  toe  look  more  projecting  than 
the  outer;  a  deviation  that  seems  principally 
to  have  originated  in  the  spread,  and  one, 
methinks,  that  has  had  more  attention  given 
it  than  any  consequences  attachable  to  it 
render  it  deserving  of.  The  quarters  range 
in  depth  from  two  to  three  inches;  and 
measure  in  thickness  from  one-fourth  to 
three-eighths  of  an  inch. 

"  The  Heels  are  the  two  protuberant  por- 
tions of  the  wall  by  which  it  is  terminated 
posteriorly.  They  are  the  shallowest,  and 
thinnest,  and  {in  connection)  only  flexible 
parts  of  the  wall.  Though  their  surfaces 
recede  from  the  perpendicular,  they  main- 
tain the  same  slope  as  the  toe  and  quarters. 
At  their  angles  of  inflection,  from  which 
are  continued  the  bars,  they  form  (in  con- 
junction with  the  heels  of  the  sole)  pouches 
or  sockets  into  which  are  received  the  heels 
of  the  sensitive  foot.  In  depth  they  range 
from  one  and  a  half  to  two  inches.  In  sub- 
stance they  do  not  exceed  a  quarter  of  an 
inch,  the  outer  heel  being  rather  thicker  than 
the  inner. 

"  The  Superior  or  Coronary  Border  is  the 
circular,  attenuated,  concavo-convex  part 
entering  into  the  composition  of  the  coronet. 
Its  extent  is  marked  exteriorly  by  the  whitish 
aspect  it  exhibits,  and  also  by  some  partial 
separation  and  eversion  of  the  outer  flakes 
of  horn  around  its  junction  with  the  wall 
below.  Externally,  it  assumes  the  same 
character  as  the  wall  below  it ;  but  its  in- 
ternal surface  is  altogether  different.  In- 
stead of  possessing  lamina?,  the  surface  is 
smooth  and  uniformly  excavated,  being 
moulded  to  the  form  of  the  sensitive  coro- 
net, and  ever3rvvhere  presenting  numerous 
pores  for  the  purpose  of  receiving  the  secret- 
ing villi.  Superiorly,  tlie  coronary  border 
presents  two  edges,  having  a  groove  be- 
tween them  for  the  reception  of  the  termi- 
nating border  of  the  cutis.  It  is  this  groove 
that  marks  the  reception  of  the  coronary 
border  into  two  parts:   the  internal  edge 


THE   HORSE. 


23 


two  surfaces.  By  one  edge  it  grows  to  the 
wall ;  the  other,  which  is  somewhat  attenu- 
ated, hangs  loose  and  floating  within  the 
cavity  of  the  hoof.  The  surfaces,  which  are 
two  lateral,  are  smooth,  and,  considering 
the  magnitude  of  the  lamella  itself,  of  enor- 
mous extent ;  so  much  so  that  it  might  be 
said  almost  to  be  constituted  entirely  of 
superficies.  And  this  leads  us  to  the  con- 
templation of  the  great  and  magnificent 
design  which  Nature  evidently  had  in  view 
in  their  formation,  viz.,  the  production  of 
ample  surface  within  a  small  space,  an  end 
that  has  been  obtained  through  the  means 
of  multiplication.  Mr.  Bracy  Clark  pro- 
cured from  the  late  Thos.  Evans,  L.L.  D., 
mathematical  teacher  of  Christ's  Hos- 
pital, a  calculation  of  what  their  united 
superficies  amounted  to ;  and  it  appeared 
to  afford  an  increase  of  actual  surface  more 
than  the  simple  internal  area  of  the  hoof 
would  give  of  about  twelve  times,  or  about 
212  square  inches,  or  nearly  one  square  foot 
and  a  half. 

"  The  lamellae  exhibit  no  differences  but 
in  their  dimensions.  In  length  they  corres- 
pond to  the  respective  depths  of  the  wall ; 
being  longest,  and  likewise  broadest,  around 
the  toe,  and  gradually  decreasing  towards 
the  hinder  parts. 

"  In  composition  they  are  horny.  Viewed 
through  a  microscope,  Mr.  Clark  discovered 
in  their  substance  two  planes  of  fibres,  '  the 
one  running  in  parallel  lines  to  the  axis  of 
the  hoof,  the  other  obliquely  intersecting 
these.'  When  stretched,  they  exhibit  signs 
of  elasticity;  but  this  appears  greater  in 
the  transverse  than  in  the  perpendicular 
direction. 

"  By  means  of  its  lamellee,  the  wall 
presents  a  superficies  of  extraordinary  am- 
plitude for  the  attachment  of  the  coffin- 
bone.  A  structure  consisting  of  similarly 
formed  lamellae  envelops  the  bone,  and  these 
are  dovetailed  in  such  a  manner  wdth  the 
horny  lamellae,  as  to  complete  a  union 
which,  for  concentrated  strength,  combining 
elasticity,  may  vie  with  any  piece  of  animal 
mechanism  at  present  known  to  us. 

"  Tlie  Bars  are  processes  of  the  wall,  in- 


flected from  its  heels  obliquely  across  the 
bottom  of  the  foot.  For  a  long  time,  by 
farriers,  they  were  confounded  with  the  sub- 
stance of  the  sole,  an  error  that  owed  its 
origin  and  perpetuation  to  the  malpractice 
they  exercised  in  paring  the  foot  —  in  cut- 
ting both  bars  and  sole  down,  without  any 
distinction,  to  a  common  level.  In  the 
natural  healthy  foot  the  bars  appear,  exter- 
nally, as  elongated  sharpened  prominences, 
extending  from  the  bases  of  the  heels  into 
the  centre  of  the  foot,  between  the  sole  and 
the  frog;  posteriorly,  they  are  continuous 
in  substance  with  the  wall,  with  which  they 
form  acute  angles ;  anteriorly,  they  stretch 
as  far  as  the  point  of  the  frog,  constituting 
two  imier  walls  or  lateral  fences  between 
that  body  and  the  sole.  Sainbel  conceives, 
from  then-  position,  that  they  offer  resistance 
to  the  contraction  of  the  heels.  Their  in- 
ternal surfaces  exhibit  rows  of  lamella, 
continued  from  those  lining  the  wall,  but 
which  are  here  short,  and  in  their  direction 
transverse,  two  cu'cumstances  referable  to 
the  narrowness  and  inflection  of  the  bar. 
Towards  the  extremity  of  the  bar  they 
gradually  grow  shorter,  and  less  distinctly 
marked,  until  we  at  length  lose  all  vestige 
of  any  more  of  them.  While  the  promi- 
nence of  the  bars  is  such  as  to  give  them  a 
secondary  bearing  upon  the  ground,  their 
sharpened  forms  will  sink  them  more  or 
less  deeply  into  every  impressible  surface. 

"  THE    SOLE. 

"  The  sole  is  the  arched  plate  entering 
into  the  formation  (as  its  name  implies)  of 
the  bottom  of  the  hoof:  or,  to  adopt  Sain- 
bel's  definition,  '  it  is  that  part  which  covers 
the  whole  inferior  surface  of  the  foot,  ex- 
cepting the  frog.'  It  is  a  very  just  practical 
observation  of  Mr.  Coleman's,  that  although 
a  knowledge  of  every  part  of  the  foot  is  in- 
dispensably necessary  to  render  us  scientific 
overseers  of  the  farrier's  art,  no  individual 
part  requires  such  undivided  attention,  as 
regards  shoeing,  as  the  sole,  since  the  suc- 
cess of  this  mechanical  operation  mainly 
depends  on  the  paring  and  defence  of  this 
arched  horny  plate. 


24 


ANATOMY   AND   PHYSIOLOGY   OF 


"  Situation  and  Connection.  —  It  fills  up 
the  interspaces  between  the  outer  and  inner 
walls  (or  bars)  of  the  crust.  I  differ  in 
opinion  from  those  who  describe  it  to  sur- 
round the  toe  of  the  frog.  I  hold  its  circum- 
ferent  support  and  connection  to  be  the  wall 
of  the  hoof,  to  wliich  it  is  firmly  cemented 
by  an  interstitial  horny  matter,  filling  the 
crevices  between  the  laminae. 

"  Figure.  —  The  circumferent  outline  of 
the  sole  measures  about  two-thirds  of  a  cir- 
cle, the  remaining  third  being  omitted  to 
form  a  triangular-shaped  hiatus  or  opening 
for  the  reception  of  the  frog  and  bars.  This 
circular  form,  however,  is  by  no  means  true, 
or  even  invariably  the  same,  in  its  dimen- 
sions. Generally,  the  longitudinal  exceeds 
the  transverse  diameter.  Its  greatest  diam- 
eter is  shown  by  a  line  extended  from  either 
heel  across  its  middle  to  the  opposite  point 
of  the  toe. 

"  Arch.  —  Commonly,  the  sole  presents 
an  arch  of  more  or  less  concavity  inferiorly, 
and  convexity  superiorly.  But  it  is  not  a 
regular  or  uniform  arch,  being  one  that 
rather  waves  or  undulates,  so  as  to  bear  a 
comparison,  made  of  it  by  Mr.  Clark,  '  to 
the  mouth  of  a  bell  extremely  extended  or 
flattened.'  Like  that  of  the  bell,  the  arch 
is  highest  in  the  middle,  from  which  it 
slopes,  laterally,  down  to  a  flat,  subsequently 
to  rise  again  around  its  border,  in  order  to 
present  a  dilated  surface  for  attachment 
towards  the  w^all.  There  is,  however,  vast 
variety  in  the  degree  of  arch  of  the  sole:  in 
some  feet  it  is  of  surprising  depth ;  in 
others,  the  arch  is  converted  into  a  flattened 
surface ;  and  yet  both  seem  to  perform 
equally  well.  In  the  hind  feet  the  sole  is 
generally  more  arched  than  in  the  fore,  and 
approaches  in  figure  nearer  to  the  oval  than 
the  circle. 

'■'■  Division.  —  In  the  sole  we  distinguish 
an  anterior  part  or  toe;  a  middle  or  central 
part ;  two  points  or  heels ;  and  two  surfaces. 
These  divisions  are  not  very  well  defined : 
but  they  prove  serviceable  in  aid  of  our  de- 
scriptions. The  toe  of  the  sole  is  the  part 
encircled  by  the  toe  of  the  wall,  against 
which  it  abuts,  and  to  which  it  is  intimately 


united  by  horny  matter,  the  two  together 
forming  a  stout  bulwark  of  defence  to  those 
parts  of  the  internal  foot  included  between 
them.  The  points  or  heels  are  the  two  pos- 
terior salient  angles  received  into  the  angu- 
lar intervals  between  the  outer  and  inner 
walls  or  bars.  Although  naturally  the 
least  exposed,  these  are  the  parts  most  sub- 
ject to  injury  or  pressure  from  the  shoe, 
being  the  seat  of  that  disease  mistakenly 
called  corn.  The  middle  or  centre  of  the 
sole  is  the  portion  more  immediately  sur- 
rounding the  fore  parts  of  the  frog,  and 
would  (were  the  sole  a  regular  arch)  be  the 
most  elevated  part ;  but,  in  general,  we  find 
the  sole  flattened  hereabouts;  the  highest 
parts  of  the  arch  being  the  angles  alongside 
of  the  bars ;  the  lowermost,  those  around 
the  toe. 

"  Surfaces.  —  Of  the  surfaces,  the  supe- 
rior (as  was  mentioned  before)  is  unevenly 
convex ;  the  inferior,  correspondently  con- 
cave. The  former  is  everywhere  pitted, 
particularly  about  the  heels,  with  numerous 
circular  pores,  running  in  an  oblique  direc- 
tion, the  marks  of  which  remain  evident 
upon  the  inferior  surface  hkewise.  These 
pores  are  the  impressions  made  in  the  soft 
horn  by  the  villi  of  the  sensitive  sole,  from 
whose  orifices  the  horny  matter  is  produced. 
They  also  form  the  bond  of  union  between 
the  horny  and  the  sensitive  soles :  which  is 
of  a  nature  so  strong  and  resisting,  that  it 
requires  the  whole  strength  of  a  man's  arm 
to  effect  their  separation  —  an  operation  of 
a  cruel  description  that  was  wont  to  be 
practised  in  times  past,  under  the  fallacious 
notion  that  '  drawing  the  sole '  was  extir- 
pating the  malady. 

"  Thickness.  —  The  natural  thickness  of 
the  sole  may  be  estimated  at  about  one- 
sixth  of  an  inch.  There  will  be  found, 
however,  variations  from  this  standard  in 
difi'erent  horses  ;  and  it  will  also  very  much 
depend  on  the  part  selected  for  measure- 
ment. The  portion  of  the  sole  most  ele- 
vated from  the  ground  —  that  w^hich  forms 
a  union  with  the  bars  —  is  nearly  double 
the  thickness  of  the  central  or  circumferent 
parts ;  and  next  to  this,  in  substance,  comes 


THE   HORSE. 


25 


the  heel.  I  do  not  find  that  the  sole  '  grows 
thinner  from  the  circumference  to  the 
centre,'  as  has  been  stated  by  an  author 
of  celebrity. 

"the  frog. 

"  The  frog  is  the  prominent,  triangular, 
spongy  body,  occupying  the  chasm  left  by 
the  inflection  of  the  bars. 

"  Situation  and  Connection.  —  The  frog 
is  fitted  into  the  interval  between  the  bars  ; 
the  three,  altogether,  filling  up  the  vacuity 
in  the  sole,  and  thereby  completing  the 
circle,  and  establishing  the  solidungulous 
character  of  the  foot.  The  frog  extends 
forward,  towards  the  toe,  about  two-thirds 
of  the  longitudinal  diameter  of  the  ground- 
surface  of  the  hoof,  terminating  a  little  be- 
yond the  central  point  (or  what  would  be 
the  central  point)  of  the  sole — or  rather 
shooting  directly  through  it,  so  as  to  anni- 
hilate the  spot.  Posteriorly,  it  is  embraced 
by  the  heels  of  the  wall;  laterally,  it  pos- 
sesses firm  and  solid  junctions  with  the 
bars,  and  through  their  medium  with  the 
sole :  and  these  unions  are  effected  not  by 
simple  apposition  and  cohesion  of  surface, 
but  by  a  lamellated  structure^  apparent  on 
the  sides  both  of  the  frog  and  bars,  by  which 
the  parts  are  reciprocally  dovetailed  into 
each  other.  Lamellae  are  discoverable  upon 
its  sides,  even  all  round  the  toe  of  the  frog ; 
and  this  is  a  circumstance  that  confirms  me 
in  my  befief  that  the  bars  reach  thus  far. 

"  Figure.  —  The  frog  may  be  called  pyra- 
midal, or  cuneiform,  or  triangular  in  figure; 
its  outline  forming  the  geometrical  figure 
denominated  an  isosceles  triangle.  I  know 
of  no  comparison  so  familiarly  apt  as  that 
of  resembling  it  to  a  ploughshare :  not  only 
do  they  both  correspond,  as  near  as  such 
comparisons  can  be  expected  to  do,  in  out- 
line and  make,  but  they  likewise  exliibit  a 
singular  coincidence  in  function ;  the  frog, 
like  the  ploughshare,  being  intended  by  its 
point  to  plough  or  divide  the  surface  of  the 
earth,  and  in  that  manner  serve  as  a  stay  or 
stop  to  the  foot. 

"  Division.  —  We  distinguish  in  the  frog- 
two  surfaces,  an  inferior  and  a  superior; 

4 


two  sides ;  a  point  or  toe ;  and  two  bulbs  or 
heels. 

"  Surfaces.  —  Both  surfaces  of  the  frog 
manifest  striking  irregularities,  and  these 
are  respectively  reversed,  making  one  sur- 
face the  exact  counterpart  of  the  other.  In 
other  respects,  the  only  difference  they  ex- 
hibit, is,  that  the  superior  exceeds  the  in- 
ferior both  in  length  and  breadth. 

"  The  inferior  surface  presents  to  our 
view  a  remarkable  cavity,  broad,  deep,  and 
triangular  in  its  shape,  bounded  on  the 
sides  by  two  sloping  prominences,  which 
divaricate  from  the  convexity  forming  the 
toe  of  the  frog,  and  terminate,  after  a  short 
divergent  course,  at  the  heels.  This  cavity 
or  hollow  is  denominated 

"  The  Cleft  of  the  Frog:  with  seeming 
reference  to  the  relationship  existing, 
through  its  presence,  between  the  horse's 
foot  and  the  cloven  one  of  the  ox,  deer, 
sheep,  etc.  In  consequence  of  its  sides 
sloping  inward,  the  cleft  at  bottom  gapes 
wide  open ;  but  along  the  top  is  roofed  by 
a  simple  linear  mark  running  from  before 
backward.  The  horn  is  kept  continually 
soft  and  pliant  within  the  cleft  by  a  pecu- 
liar secretion  from  the  sensitive  parts  it 
covers,  the  odor  of  which  is  notorious. 

"  The  solid  wedge-like  portion  of  horn 
in  front  of  the  cleft,  extending  from  it  to 
the  point  of  the  toe,  has  been  observed  by 
Mr.  Clark  to  exhibit,  in  the  natural  foot  at 
its  full  growth,  '  a  considerable  bulbous  en- 
largement,' which,  by  way  of  distinction, 
he  calls  the  cushion  of  the  frog.  On  making 
a  perpendicular  section  of  the  foot,  JVIr.  C. 
finds  this  part  is  situated  '  nearly  opposite 
or  under  the  navicular  bone.'  And  it  would 
appear  (according  to  this  author)  that  this 
'rotundity,  or  swell  of  the  frog,'  is  never 
reproduced  after  it  has  once  been  annihi- 
lated by  the  knife  of  the  smith. 

"  The  superior  surface  of  the  frog,  every- 
where continuous,  uniform,  and  porous, 
being  the  counterpart  in  form  of  the  infe- 
rior, presents  us  with  nothing  but  reverses : 
where  the  one  is  hoUow  or  depressed  the 
other  rises  into  swells  and  eminences,  and 
vice  versa.     This  accounts  for  our  finding 


26 


ANATOMY   AND   PHYSIOLOGY   OF 


the  part  opposite  to  the  cleft  elevated  into 
a  conspicuous  eminence,  bounded  on  its 
sides  by  two  deep  channels,  and  a  hollow 
of  broader  but  shallower  dimensions  in  the 
front.  To  this  central  conical  elevation 
]\Ir.  Clark  has  given  the  name  of  frog-slay, 
from  some  novel  notions  he  entertains  of  its 
physiology.  Such  a  bold  promontory  of 
horn  rising  in  the  middle  of  broad  and 
deep  channels  is  well  calculated  to  form 
that  dovetailed  sort  of  connection  with  the 
sensitive  foot,  which  greatly  augments  their 
surfaces  of  apposition,  and  establishes  their 
union  beyond  all  risk  or  possibility  of  dislo- 
cation. It  is  a  part  which  (as  far  as  my 
observations  on  it  have  extended)  grows 
and  becomes  developed  together  with  other 
parts  of  the  foot ;  and  one  that  is  apt  to 
vary  in  its  relative  volume  in  different  feet. 
In  front  of  the  frog-stay,  the  lateral  borders, 
bounding  the  hollow  in  the  middle,  describe 
a  waving  line,  which,  near  half-way  to  the 
point  of  the  toe,  exhibits  a  dip  or  impres- 
sion :  this  marks  the  impression  of  the 
navicular  bone,  and  is  the  part  immediately 
opposite  to  the  '  cushion  of  the  frog,'  —  a 
coincidence  important  to  be  borne  in  mind, 
as  tending  to  throw  some  light  on  the  na- 
ture of  this  new-christened  structure.* 

"  The  Sides  are  the  parts  by  which  the 
frog  establishes  its  union  with  the  borders 
of  the  triangular  vacuity  in  the  hoof  into 
which  it  is  admitted.  Along  their  superior 
borders  they  are  transversely  lamellated,  or 
rather  indentated,  in  order  that  they  may  be 
fitted  to  the  internal  surfaces  of  the  bars, 
which  exhibit  a  similar  structure. 

"  The  Commissures  are  the  two  deep 
triangular-shaped  hollows  between  the  bars 
and  the  sides  of  the  frog.  It  being  only 
the  superior  borders  of  these  parts  that  are 
engaged  in  their  union,  their  broad,  unat- 
tached parts,  below,  form  the  boundary 
walls  of  the  commissures.  Looking  into 
the  interior  of  the  hoof,  we  discover  that 
the  commissures,  internally,  are  converted 
into  rounded  promontories,  similar  in  ap- 

*  In  fact,  the  cushion  of  the  frog  appears  to  be  nothing 
more  than  a  bulge  of  the  part  produced  by  the  superin- 
cumbent pressure  of  the  navicular  bone. 


pearance  and  texture  to  the  one  in  the  mid- 
dle—  the  frog-stay  —  on  the  sides  of  which 
they  are  rising.  In  the  natural  state, 
the  commissures  must  unavoidably  get 
plugged  with  dirt,  or  whatever  the  animal 
may  happen  to  tread  upon  ;  a  circumstance 
from  w^hich  some  far-fetched  notions  have 
been  extracted  concerning  their  use. 

"  The  Toe  or  point  of  the  frog  is  the  ante- 
rior, undivided,  elongated  portion;  that  which 
forms  the  apex  of  the  pyramid  or  wedge  — 
the  acute  or  extended  angle  of  the  triangle 
—  the  only  part  displaying  that  prominent 
or  rounded  form  that  would  warrant  us  in 
using  the  epithet  '  conical '  to  the  frog.  It 
possesses  sohdity  of  substance,  firmness  of 
texture,  and  luxuriance  of  growth  in  an 
eminent  degree  ;  facts  well  known  to  the 
farrier,  who,  in  paring  the  foot,  seldom  fails 
to  make  more  free  with  this  than  any  other 
part  of  the  frog. 

"  The  Heels  or  bulbs  of  the  frog  are  the 
posterior  protuberant  parts  embraced  by  the 
heels  of  the  wall,  and  separated  from  each 
other  by  the  cleft,  forming,  together,  the 
base  of  the  wedge  or  triangle.  They  pre- 
sent greater  depth  of  substance  than  the 
toe,  but  are  of  a  softer,  more  spongy  tex- 
ture, and  are  less  resisting  and  stable,  in 
consequence  of  being  deprived  of  mutual 
support  by  the  division  of  the  cleft.  Ante- 
riorly, the  heels  unite  with  the  lateral  promi- 
nences bounding  the  cleft ;  inferiorly,  they 
present  two  surfaces  of  tread  to  the  ground, 
eivdently  designed  to  take  a  share  in  the 
bearing  of  the  foot ;  posteriorly  and  supe- 
riorly, they  exhibit  a  bulbous  fulness,  in 
consequence  of  receiving  at  this  part  a  sup- 
plementary covering  from  a  production 
which  has  been  (in  the  description  of  the 
wall)  adverted  to,  under  the  appellation 
given  it  by  Mr.  Clark,  of 

"  Coronary  Frog-band.  —  It  was  there 
stated,  that  the  coronary  groove  (the  groove 
or  canal  in  the  coronary  border  of  the  cutis) 
broadened  considerably  as  it  descended  to 
and  turned  round  upon  the  heels  ;  in  like 
manner  does  the  horny  band  produced  by 
it  broaden,  and  not  only  grow  broader  but 
thicker  in  substance,  and  consequently  in 


THE   HORSE. 


27 


the  same  degree  augments  the  substance  of 
the  heels,  occasioning  that  swell  of  them 
which  has  suggested  the  appellation  '  bulb.' 
The  horny  band  itself  is  everywhere  lamel- 
lated  upon  its  internal  surface ;  but  these 
broadened  parts  of  it  display  lamellse  of  a 
much  bolder  character,  and  consequently 
render  their  union  with  the  heels  so  much 
the  more  intimate  and  enduring.  The  in- 
ferior edge  of  the  band  is  denticulated,  and 
the  denticulations  become  so  interlaced 
with  the  lamellated  fibres  of  the  wall,  that 
their  union  is  rendered,  in  the  ordinary 
state  of  the  hoof,  altogether  imperceptible. 
For  drawing  our  attention  to  this  part^we 
are  indebted  to  JVIr.  Clark;  and,  insomuch 
as  he  considers  it  to  be  a  production  of  the 
cutis  (not  having  any  connection  with  the 
glandular  circle  that  secretes  the  wall),  and 
to  serve  the  purpose  of  *  uniting  the  sensible 
parts  with  the  insensible,'  I  agree  with  him. 
I  find  something  very  similar  to  this  grow- 
ing upon  the  human  nail,  issuing  from  the 
superior  edge  of  the  terminating  border  of 
the  cutis,  and  continued  from  the  cuticle, 
which  proceeds  for  some  way  upon  the  nail, 
uniting  it  more  closely  and  firmly  with  the 
cutis,  and  protecting  the  latter  from  exter- 
nal injury.  This  production  is  no  more  the 
beginning  of  the  nail  itself  than  is  the  so- 
called /roo'-band  the  commencement  of  the 
wall :  they  are  both  distinct  parts,  though 
but  supplementary  ones,  and  seem  to  be  of 
a  nature  partaking  both  of  horn  and  cuti- 
cle. It  has  no  more  important  relation  to 
the  frog,  in  my  opinion,  than  it  has  to  the 
wall :  it  serves  the  same  purpose  to  both, 
—  that  of  strapping  up  the  heels  of  the 
frog  and  binding  them  in  closer  and  more 
intimate  connection  with  the  neighboring 
parts.  Were  I  asked  what  other  use  it  ap- 
peared to  have,  I  should  say,  that  it  was 
formed  to  cover  and  protect  from  injury  the 
neW'for?ned  horn  of  the  hoof,  guarding  it  in 
its  passage  downward,  until  it  has  acquired 
substance  and  hardness  sujEficient  to  resist 
external  impressions  of  itself. 

"development  of  the    hoof. 
"  During  the  early  months  of  fcEtality,  no 


horn  or  hoof  is  to  be  found.  The  foot  is 
covered  with  a  substance,  white,  firm,  and 
elastic,  resembling  cartilage  in  its  appear- 
ance, but  proving  more  of  the  nature  of 
cuticle  on  examination,  which  supplies  the 
place  of  hoof.  At  the  coronet  this  substance 
takes  its  origin  from  the  cutis,  being  found 
to  be  continuous  with  the  cuticle  ;  but  that 
which  covers  the  bottom  of  the  foot  is  a 
production  firom  the  sensitive  sole  and  frog. 
Altogether,  it  possesses  the  general  form 
and  appearance  of  the  hoof,  differing  how- 
ever in  these  particulars — that  the  sub- 
stitute for  the  wall  is  comparatively  thin  in 
its  substance ;  while  that  which  grows  from 
the  bottom  of  the  foot  is  enormously  thick, 
and,  instead  of  being  shaped  into  sole  and 
frog,  exuberates  to  a  degree  to  constitute 
club-footedness.  About  the  same  period 
at  which  the  pastern  and  coffin-bones  take 
on  ossification,  horn  makes  its  appearance 
underneath  this  cuticular  wall,  in  the  form 
of  plates  descending  from  the  coronet,  ex- 
hibiting with  peculiar  distinctness  the  lamel- 
lated structure.  The  horny  wall  becomes 
considerably  advanced  before  we  perceive 
any  change  in  the  bottom  of  the  foot.  At 
length,  horn  is  detected  forming  underneath 
the  cuticular  substance,  which,  increasing  in 
thickness,  gradually  represents  sole  and  frog. 
Not,  however,  in  an  undeveloped  state^  for 
even  at  birth  these  parts  are  yet  concealed 
by  the  exuberant  cuticular  covering,  now 
become  loose  in  its  texture,  and  shaggy  and 
ragged,  in  consequence  of  not  receiving  any 
further  supply  from  the  parts  that  produced 
it,  and  of  being  near  its  decadence ;  for  it 
not  long  after  falls  off,  disclosing  sole  and 
frog  both  ready  formed. 

"structure  of  the  hoof. 
"  Horn  is  found  to  differ  in  its  texture  or 
quality,  not  only  in  the  many  animals  in 
which  it  is  met  with,  but  in  different  parts, 
and  even  in  the  same  part  of  the  body  of 
the  same  animal.  That  which  composes 
the  hoof  of  the  horse  is  a  remarkable  ex- 
ample of  this.  How  different  is  the  horn 
of  the  frog  from  the  horn  of  the  wall ;  and 
yet  neither  of  them  agree  in  texture  with 


28 


ANATOMY   AND   PHYSIOLOGY   OF 


the  sole.  The  horny  substance  of  the  wall 
is  resolvable  into  fibres,  bearing  a  resem- 
blance to  thick  or  coarse  hairs,  wliich  in  the 
entire  hoof  are  so  intimately  matted  and 
glued  together,  as  to  have  the  appearance 
and  strength  of  solidity.  By  close  and  ac- 
curate inspection  these  fibres  may  be  seen 
descending  in  parallel  lines,  taking  the 
obliquity  of  the  wall,  from  the  coronet  to 
the  inferior  or  solar  border ;  they  do  not  run 
promiscuously,  but  are  arranged  in  rows, 
forming  sorts  of  beds  or  strata,  lying  one 
upon  another — a  disposition  made  manifest 
in  the  foot  of  the  foetus.  A  clean-cut  trans- 
verse section  of  the  wall  exhibits  upon  its 
surface  numerous  minute,  circular,  whitish 
spots,  which  grow  larger  and  more  distinct 
towards  the  internal  part,  and  through  a 
glass  appear  to  be  hollow  or  tubular. 
These  spots  I  take  to  be  produced  by  sec- 
tions of  the  horny  tubes,  apparently  contain- 
ing a  whitish  matter,  a  sort  of  pith,  or  pulp, 
or  gelatinous  instillation  which  pervades 
them  from  their  origin  from  the  villi  of  the 
coronary  circle ;  the  same  as  hairs  derive 
their  unctuous  matter  from  the  bulbs  pro- 
ducing them,  and  (as  this  matter  does  the 
hair)  renders  the  horny  fibre  tough  and 
elastic — in  fact,  imbues  it  with  the  peculiar 
attributes  so  well  known  to  smiths  by  the 
appellation  of  living'  horn ;  the  epithet 
"  living  "  being  here  used  to  denote  the  ob- 
vious differences  the  hoof  of  a  living  animal 
evinces  from  one  that  has  been  long  detached 
from  the  body,  or  that  is  dead.  We  are  too 
apt  to  believe  that  the  various  agents  known 
to  act  upon  the  dead  hoof  or  horn  must 
take  similar  effect  on  the  living ;  and  upon 
this  erroneous  belief  we  employ  hot  and 
cold  water,  etc.,  etc.,  in  treating  disease  of 
the  feet,  forgetting  that  we  have  opposed  to 
our  remedies  the  resisting  or  self-preserving 
properties  of  living  horn. 

"  The  sole,  as  well  as  the  wall,  is  fibrous 
in  its  structure ;  but  its  fibres  appear  to  be 
of  a  finer  quality,  and,  in  course,  are  very 
much  shorter :  they,  however,  take  an  ob- 
lique direction,  from  behind  forwards,  fol- 
lowing the  same  degree  of  slope  as  those 
of   the  wall.     They   issue   from   the   villi 


penetrating  the  superior  surface.  To  the 
fineness  of  its  fibres,  combined  with  the  rel- 
ative magnitude  of  the  tubular  canals,  and 
consequent  proportions  of  horny  and  gela- 
tinous substances,  may  be  ascribed  the 
comparative  softness  and  elasticity  of  the 
sole. 

"  The  frog,  however,  displays  these 
qualities  in  such  a  remarkable  degree  as  to 
appear,  in  fact,  to  be  composed  of  quite 
another  kind  of  horn  ;  though,  on  examina- 
tion, we  find  it  to  evince  the  same  fibrous 
structure,  the  only  perceivable  differences 
being  the  comparative  fineness  of  the  fibres 
and  their  proportionably  greater  tubularity : 
their  direction  is  oblique,  correspondent  with 
those  of  the  wall. 

"production  of  the  hoof. 

"  The  wall  is  produced  by  the  coronary 
substance,  a  sensitive  and  glandular  part  we 
shall  have  occasion  soon  to  examine.  Its 
villi,  by  some  peculiar,  mysterious,  secretory 
process,  convert  the  blood  circulating 
through  them  into  a  soft  pulpy  gelatinous 
matter,  which  by  exposure  becomes  hard 
horn, descending  from  the  villous  point  that 
produced  it,  in  the  form  of  a  tubular  fibre, 
down  to  the  sole.  The  fibres  are  united 
together  at  their  very  origin,  but  their  tubes 
or  canals  diminish,  the  lower  they  descend ; 
which  accounts  for  the  porous  or  honey- 
comb-like structure  of  the  interior  of  the 
coronary  border  and  the  comparative  solidity 
of  the  parts  below.  The  outer  layers  or 
strata  of  fibres  are  found  to  be  more  com- 
pact and  of  closer  texture  than  the  inner; 
which  arises,  in  part,  from  the  villi  produc- 
ing them  being  removed  to  a  greater  dis- 
tance, and  to  the  comparative  smallness  of 
their  canals,  and  which,  consequently,  the 
sooner  become  obliterated.  The  use  of 
Mr.  Clark's  coronary  frog-band  becomes 
now  more  apparent,  serving,  as  it  evidently 
does,  to  cover  and  protect  these  external 
fibres  until  they  grow  sufficiently  firm  and 
solid  of  themselves  to  bear  exposure  and 
resist  casualties. 

"  The  sensitive  laminae  make  no  addition 
to  the  substance  or  thickness  of  the  wall : 


THE  HORSE. 


29 


they  simply  produce  the  horny  lamella 
arranged  along  its  interior;  as  one  proof 
of  which,  the  wall  measures  as  much  in 
thickness  at  the  place  where  it  quits  the 
coronet  as  it  does  at  any  point  lower  down. 
Other  demonstrations  of  this  fact  come 
every  day  before  such  practitioners  as  have 
to  treat  canker,  qmttor,  sandcrack,  and 
other  diseases  of  the  feet. 

"  The  horny  sole  is  a  production  from  the 
villi  of  the  sensitive  sole  ;  after  the  same 
process  as  that  by  which  the  horny  frog  is 
secreted  from  the  villi  of  the  sensitive  frog. 

"  In  a  state  of  health  of  the  foot,  the  se- 
cretion of  horn  is  unceasingly  going  on. 
Disease  or  injury  of  the  glandular  parts  may 
diminish  or  altogether  suspend  the  process ; 
disease,  under  certain  other  forms,  appears 
also  to  have  the  effect  of  increasing  it ;  but 
whether  we  have  any  artificial  means  of 
effecting  this,  seems  questionable.  The 
wall  grows  from  above  downwards.  If  a 
mark  be  made  in  any  part  of  the  wall,  it 
will  remain  until  it  grows  down  and  be- 
comes cut  off  below,  at  the  inferior  border ; 
and  by  observations  made  on  the  gradual 
descent  and  disappearance  of  these  marks, 
calculations  may  be  formed  of  the  period 
of  time  required  for  the  renewal  or  restora- 
tion of  the  wall. 

"  PROPERTIES    OF    HORN. 

"  Horn  is  a  tough,  flexible,  elastic  sub- 
stance, consisting  of  tubular  fibres,  more  or 
less  intimately  connected  together,  taking 
the  direction  from  the  surface  of  the  body 
on  which  it  grows.  Its  property  of  tough- 
ness or  resistance  much  depends  on  its  con- 
dition in  regard  to  moisture ;  for  if  it  is 
exposed  to  a  degree  of  heat  sufficient  to 
abstract  much  of  its  natural  juice  or  imbibed 
moisture,  it  loses  its  flexibility  and  tough- 
ness, and  becomes  brittle.  On  the  other 
hand,  saturated  with  moisture,  it  is  con- 
verted into  a  soft  and  highly  flexible  sub- 
stance, but  at  the  same  time  becomes  weak 
and  unresisting.  This  known  effect  aids  us 
to  account  for  the  flat-footedness  of  horses 
reared  in  low,  fenny,  or  marshy  situations ; 
the   hoof  being  constantly  in   a   state   of 


saturation  with  moisture,  the  wall  and  sole 
yield  to  the  superincumbent  burthen  of  the 
body,  and  the  latter  grows  flat  (instead  of 
remaining  concave  or  arched),  and  even  in 
some  instances  bulges.  If  oily  or  unctuous 
applications  have  any  effect  in  softening  the 
hoof,  they  appear  to  do  so  by  filling  the 
crevices  and  interstices  between  the  fibres 
on  the  surface,  and  in  this  manner  checking 
or  suppressing  evaporation.  Horn  takes  a 
high  and  beautiful  polish.  Although  much 
inferior  in  transparency  to  tortoise-shell,  it 
may  be  worked  up  to  bear  so  near  a  resem- 
blance to  it  as  to  be  often,  in  manufactures, 
substituted  for  it,  as  in  combs,  etc.  The 
hoof  admits  of  an  elegant  polish ;  and  in 
that  altered  and  improved  state  has  been 
manufactured  into  articles  no  less  useful 
than  valuable  and  ornamental :  *  even  the 
hoofs  of  the  living  animal  may,  by  being 
kept  clean,  and  when  dry  rubbed  with  lin- 
seed oil,  be  numbered  among  the  ornamen- 
tal beauties  Nature  has  bestowed  upon 
quadrupeds. 

"  By  chemical  analysis  horn  has  been 
found  to  consist  of  membranous  substance, 
having  the  properties  of  coagulated  albumen, 
and  of  some  gelatine.  The  horns  of  some 
animals,  the  deer  species,  from  containing 
bone,  become  exceptions  to  this.  Mr. 
Hatchett  burn"  ^ve  hundred  grains  of  ox's 
horn,  and  the  residuum  proved  only  one 
and  a  half  grain,  not  half  of  which  was 
phosphate  of  lime. 

"  Shavings  of  hoof  thrown  into  nitric 
acid  become  soft,  and  speedily  melt  into  a 
yellow  mass,  which  in  about  eight  hours 
disappear  in  complete  solution. 

"  The  same  thrown  into  sulphuric  acid 
turn  black,  in  becoming  soft,  and  require 
thrice  the  time  for  their  solution.  Muriatic 
acid  also  turns  horn  black,  and  corrodes 
it,  but  has  so  little  effect  towards  its  solu- 
tion, that  after  ten  days  a  piece  of  hoof 
soaked  in  it  was  found  to  have  become  only 
more  brittle  or  rotten.  Common  vinegar 
will  turn  horn  dark-colored,  but  does  not 

*  The  Eclipse  hoof,  presented  by  his  Majesty  at  Ascot 
Races,  as  tlie  reward  of  the  best  horse  on  the  turf,  forms 
a  notable  illustration  of  this. 


30 


ANATOMY   AND    PHYSIOLOGY    OF 


appear  to  have  any  power  in  impairing  its 
texture,  or,  at  least,  in  dissolving  it.  Liquor 
potassEB  will  not  only  turn  it  black,  but  will 
corrode  the  horn  of  the  hoof.  Ammonia 
does  not  change  its  color,  but  slowly  destroys 
its  texture,  rendering  it  brittle  and  rotten. 

"INTERNAL   PARTS    OF   THE 
FOOT. 

"  The  internal,  sensitive,  organic  parts  of 
the  foot,  comprise  the  bones,  ligaments,  ten- 
dons, coronary  substance,  cartilages,  sensitive 
lamince,  sensitive  sole,  and  sensitive  frog. 

"  The  bones  entering  into  the  composition 
of  the  foot  are  the  coffin  and  navicular 
bones :  to  which  may  be  added  (as  forming 
part  of  the  coffin-joint,  and  consequently 
having  intimate  relation  to  them),  the  coro- 
net bojie. 

"  The  tendons  immediately  connected 
with  the  foot  are  those  of  the  extensor  pedis 
and  the  flexor  pedis  perforans :  the  former 
being  inserted  into  the  coronal  process ;  the 
latter  into  the  posterior  concavity  of  the 
coffin-bone. 

"the  coronary  substance. 

"  A  less  inappropriate  name  for  the  part 
commonly  called  the  coronary  ligament* 

"  To  revert,  for  the  sake  of  elucidation 
here,  to  former  description --nfter  the  hoof 
has  been  detached  by  a  process  of  macera- 
tion or  putrefaction,  in  a  perfectly  entire, 
uninjured  condition,  it  presents  around  its 
summit  a  circular  groove,  bounded  in  front 
by  a  soft  whitish  substance,  having  a  thin 
edge,  and  being  of  a  nature  between  horn 
and  cuticle ;  and  behind,  by  an  attenuated 
margin,  more  horny  in  its  character,  whose 
thin  edging  is  denticulated  or  serrated.  Into 
this  circular  groove  or  canal  is  received  the 
terminating  margin  of  the  cutis :  the  cuti- 
culo-horny  layer  of  the  hoof,  in  front  of  it, 
having  every  appearance  of  being  a  continu- 
ation of  the  cuticle. 

"  Situation — Dimension. — The  coronary 

*  Averse  as  I  am  to  changing  or  altering  names,  noth- 
ing less  than  a  palpable  contradiction,  in  regard  both  to 
structure  and  function,  would  have  induced  me  to  do  so  in 
the  present  instance. 


substance  occupies  the  concavity  formed 
upon  the  inside  of  the  superior  or  coronary 
border  of  the  wall  of  the  hoof:  it  is  the 
part  constituting  the  basis  of  the  circular 
prominence  commonly  distinguished  in  the 
living  animal  as  the  coronet.  It  is  broadest 
around  the  toe  of  the  wall,  diminishing  in 
breadth  towards  the  quarters  and  heels,  and 
being  somewhat  broader  around  the  outer 
than  the  inner  side.  It  is  thickest  in  sub- 
stance around  its  middle  and  most  promi- 
nent parts,  growing  gradually  thinner  both 
above  and  below. 

"  Connection.  —  Externally,  the  coronary 
substance  is  connected  with  the  hoof;  and 
the  connection  appears  to  be  principally,  if 
not  entirely,  of  a  vascular  nature :  the  sur- 
face of  the  wall  presenting  a  porous  honey- 
comb-like texture,  and  the  villi  or  vessels 
issuing  from  the  coronary  substance  enter- 
ing the  pores,  and  thus  establishing  an  inti- 
mate and  extensive  vascular  union  between 
these  organic  and  inorganic  parts.  Inter- 
nally, the  coronary  substance  is  connected 
with  the  coffin-bone,  the  extensor  tendon, 
and  the  cartilages,  by  a  fine,  dense,  copious 
cellular  tissue,  which  at  the  same  time  forms 
a  bed  for  the  assemblage  and  ramification  of 
the  blood-vessels  concerned  in  the  secretion 
of  the  wall  of  the  hoof.  Superiorly,  its 
union  with  the  skin  is  so  intimate  and  com- 
plete, that  one  has  been  thought  to  be  a 
continuation  of  the  other ;  and,  so  far  as 
meets  the  eye  of  a  common  observer,  they 
might  be  taken  as  such ;  but,  when  we 
come  to  examine  them  by  anatomical  tests, 
we  not  only  find  a  line  of  external  demar- 
cation between  them,  but  discover  such 
difference  of  internal  structure  as  forbids 
the  adoption  of  this  delusive  notion.  As  it 
descends  upon  the  coffin-bone,  the  coronary 
substance  not  only  grows  thinner,  but  in 
growing  attenuated  becomes  imperceptibly 
gathered  or  puckered  into  numerous  points, 
from  which  issue  a  like  number  of  plaits  or 
folds,  which  afterwards  form  the  sensitive 
laminae.  It  is  worthy  of  remark,  that  the 
part  of  the  bone  upon  which  this  transfor- 
mation takes  place  is  smaller  in  circumfer- 
ence than  the  coronet;    consequently  the 


^ 


EXPLANATION   OF   FIGURE  IV. 


NO.    1.  — OSSEOUS  STRUCTURE. 

OFF-HIND  EXTREMITY. 

22.  Femur  or  thigh  bone.  , 

23.  Patella. 

24.  Tibia. 

25.  Os  calcis. 

26.  Astragalus. 

27.  One  of  the  tarsal  bones. 

28.  Metatarsus  magnum. 

29.  The  sessamoids. 

30.  Os  sufiraginis. 

31.  Os  corona. 

32.  Os  pedis.  ' 
e.  The  fibula. 

The  above  explanation  will  answer  for  "No.  3,"  of  this  plate. 

NO.   2.  —  MUSCULAR  STRUCTURE. 

SIDE  VIEW  OF  THE  OFF-HIND  EXTREMITY. 

j.    Triceps. 

n.    Rectus. 

o'.    Vastus. 

r.  s\  Gastrocnemi,  and  perforans. 

V.  V.    Flexor  pedis  accessorius. 

u'.    (At  the  hock.)    The  insertion  of  the  gastrocnemius  into  the  point  of  the  hock. 

x'.    Extensor  pedis. 

y.  y\  Peroneus. 

V.    (Beneath  the  pastern.)     Flexor  perforatus  and  perforans. 

z.     Bifui-cation  of  the  suspensory  ligament. 

Sr.    The  hoof. 

8.     One  tendon  of  the  suspensory  ligaments. 

NO.   4.    MUSCULAR  STRUCTURE. 

ANTERIOR  VIEW  OF  THE  OFF  HIND  EXTREMITY. 

n.    Rectus. 

o'.    Vastus  extemus. 

J.    Triceps  abductor  tibialis. 

y.  y\  Peroneus. 

x'.  x\  Extensor  pedis. 

g.    Flexor  pedis  accessorius. 

8.    Bifurcation  of  the  suspensbry  ligament. 

5.     Saphena  vein. 

^.    The  hoof. 


THE  HOESE. 


31 


same  measure  of  coronary  substance  which 
but  tensely  and  smoothly  covered  the  latter, 
admitted  of  being  disposed  in  gathers  or 
folds  so  soon  as  it  reached  the  former.  Pos- 
teriorly, the  coronary  substance  forms  a 
junction,  indeed  becomes  continuous  in 
substance,  with  the  heels  of  the  sensitive 
frog. 

"  Structure.  —  The  coronary  substance 
discloses  three  different  parts  in  its  com- 
position :  1.  A  fibro-cartilaginous  circling 
band,  forming  the  substratum  and  basis  of 
the  entire  structure.  2.  A  cuticular  cover- 
ing, so  called  from  its  resemblance  in  tex- 
ture to  the  cutis.  3.  A  network  of  blood- 
vessels, reposing  upon  the  former,  and 
covered  by  the  latter.  The  cartilaginous 
structure,  freed  from  its  vascular  connec- 
tions, is  found  to  be  wrought  in  the  form 
of  a  coarse,  open,  irregular  network,  and 
appears  designed  mainly  for  the  purpose  of 
affording  a  bed  for  the  lodgment  and  rami- 
fication of  the  blood-vessels  destined  to  pror 
duce  the  wall.  The  looseness  of  its  con- 
nection, added  to  its  own  elasticity,  renders 
this  substance  peculiarly  adapted  to  accom- 
modate itself  to  the  motions  of  the  coffin- 
joint,  and  thus  preventing  those  movements 
from  operating  prejudicially  to  the  super- 
imposed glandular  structure. 

"  Organization.  —  The  coronary  sub- 
stance may  be  ranked  among  the  most  vas- 
cular parts  of  the  body :  no  gland  even 
possesses,  for  its  magnitude,  a  greater  abun- 
dance of  blood-vessels,  or  of  blood-vessels 
(taking  them  generally)  of  larger  size  ;  nor 
does  there  exist  any  part  in  which  greater 
care  appears  to  have  been  taken  to  arrange 
its  vessels  so  as  to  insure  an  uninterrupted 
supply  of  blood.  These  vessels  it  is  that 
produce  the  wall :  and  there  is  every  reason 
to  believe  that  they  perform  this  office 
without  any  assistance  from  the  vessels  of 
the  laminae. 

"  THE    CARTILAGES 

"  Are  two  broad,  scabrous,  concavo-con- 
vex, cartilaginous  plates,  erected  upon  the 
sides  and  wings  of  the  coffin-bone.  Pro- 
fessor Coleman  calls  them  '  the  lateral  car- 


tilages,' in  contradistinction  to  two  others 
he  has  named  '  the  inferior  cartilages.' 

"  Situation.  —  The  cartilages  form  the 
postero-lateral  parts  of  the  sensitive  foot, 
extending  the  surface  considerably  in  both 
these  directions. 

"  Attachment.  —  The  cartilages  are  fixed 
into  fossa?  excavated  in  the  supero-lateral 
borders  of  the  coffin-bone.  Their  anterior 
parts  become  united,  on  each  side,  with 
descending  lateral  expansions  from  the  ex- 
tensor tendon,  and  are  also  attached  to  the 
coronet  bone  by  cellular  membrane.  Their 
posterior  parts  surmount  the  al(B  or  wings 
of  the  bone,  to  which  they  are  firmly  fixed, 
and  from  which  they  project  backwards, 
beyond  the  bone,  giving  form  and  substance 
to  the  heel.  Supposing  one  of  the  carti- 
lages to  be  divided  into  two  equal  parts  by 
a  line  drawn  horizontally  across  its  middle, 
the  superior  half,  which  extends  as  high  as 
the  pastern-joint,  is  covered  by  skin  only; 
and  on  that  account  is  quite  perceptible  to 
the  feel,  and  (in  form)  to  the  sight,  as  the 
animal  stands  with  his  side  towards  us. 
The  lower  half  is  covered,  superiorly,  by 
the  encircling  coronary  substance ;  inferiorly, 
by  sensitive  laminae  :  consequently,  over  all 
by  the  hoof,  which  envelopes  both  the  coro- 
nary substance  and  the  laminae.  The  ex- 
treme posterior  ends  of  the  cartilages  incur- 
vate  downward  and  backward ;  but,  being 
overreached  by  the  heels  of  the  sensitive 
frog,  any  abrupt  or  exposed  termination  of 
them  is  prevented.  Around  these  points 
also  the  coronary  substance  makes  its  in- 
flections upon  the  sensitive  frog,  thereby 
giving  them  additional  substance  and  sup- 
port. 

"  Form.  —  Considered  in  the  detached 
state,  the  cartilage  in  its  general  figure  de- 
scribes an  irregular  quadrangle,  of  which 
the  supero-anterior  and  infero-posterior  an- 
gles are  the  most  projecting ;  the  latter  at 
the  same  time  being  incurvated  inwards. 
Externally,  the  cartilage  is  pretty  regularly 
convex;  internally,  it  is  unevenly  concave, 
the  surrounding  border  turning  inwards  into 
the  substance  of  the  sensitive  frog.  The 
posterior  part  of  the  cartilage  is  somewhat 


32 


ANATOMY   AND   PHYSIOLOGY  OF 


thinner  than  the  anterior,  and  has  several 
foramina  through  it  —  three  or  four  of 
large  size  —  which  transmit  vessels  to  the 
frog. 

"  The  False  Cartilages.  —  From  the  in- 
ferior and  posterior  sides  of  the  true  carti- 
lages, proceed  in  a  direction  forward  — 
towards  the  heels  of  the  coffin-bone  —  two 
fibro-cartilaginous  productions,  to  which 
Mr.  Coleman  has  given  the  name  of  '  infe- 
rior cartilages.'  If  they  are  to  be  consid- 
ered as  cartilages  at  all,  I  prefer  denomi- 
nating them  false ;  they  being,  as  well  in 
structure  as  in  use,  different  from  the  true 
or  lateral  cartilages.  They  spread  inwards 
upon  the  surface  of  the  tendo  perforans ; 
become  united  at  their  inner  sides  with  the 
superior  margin  of  the  sensitive  frog ;  are 
covered  inferiorly  by  the  sensitive  sole ;  and 
at  the  same  time  assist  in  the  support  of 
the  sensitive  frog.  They  are  triangular  in 
their  figure,  and  are  arched  in  the  same 
manner  as  the  sole. 

"  Use.  —  Their  use  appears  to  me  to  be, 
to  fill  up  the  triangular  vacant  spaces  left 
between  the  tendo  perforans  and  heels  of 
the  coffin-bone,  thereby  completing  the  sur- 
face of  support  for  the  sensitive  frog,  and 
extending  that  for  the  expansion  of  the 
sensitive  sole.  Bone  in  these  places  must 
have  proved  inconvenient  by  more  or  less 
impeding  the  impression  upon,  and  con- 
sequent reaction  of,  the  sensitive  frog. 

"the  sensitive  lamina  or  lamella. 

"  So  is  denominated  the  laminated,  mem- 
branous, vascular  structure  clothing  the  wall 
of  the  coffin-bone. 

"  Production.  —  The  sensitive  laminas 
appear  to  be  derived  from  the  coronary  sub- 
stance —  the  one,  in  fact,  seems  to  be  a  con- 
tinuation from  the  other ;  for  if,  in  a  foot  in  a 
putrid  condition,  we  attempt  to  part  them 
by  force,  we  may  make  an  artificial  rent 
somewhere,  but  can  find  no  natural  separa- 
tion between  them.  The  cuticular  covering 
of  the  coronary  substance  having  descended 
upon  the  coffin-bone,  the  circumference  of 
which  is  less  than  that  of  the  coronet,  be- 
cause thereupon   gathered  into  numerous 


fittle  plaits  or  folds,  which  proceed  in  paral- 
lel slanting  lines  down  the  wall  of  the  bone : 
a  transformation  it  may  be  difficult  to  ex- 
plain, since  the  lamina?  unfolded  would 
occupy  a  much  larger  surface  than  the 
coronet ;  at  the  same  time,  it  is  one  that 
has  its  parallels  in  the  animal  constitution, 
and  a  remarkable  one  in  the  instance  of  the 
ciliary  processes. 

"  Division.  —  According  to  this  mode  of 
derivation,  every  lamina  consists  of  one 
entire  plait  or  duplication  of  substance, 
having  its  imvard  sides  intimately  and  in- 
separably united ;  its  outivard  sides  being 
the  surfaces  of  attachment  for  the  horny 
lamiuEB.  It  has  also  two  borders :  one  op- 
posed to  the  coffin-bone,  the  other  to  the 
hoof ;  and  two  ends  or  extremities,  one  issu- 
ing out  of  the  coronary  substance,  the 
other  vanishing  in  the  sensitive  sole. 

"  Structure.  —  The  substance  of  the  la- 
minae when  held  to  the  light  evinces  a 
degree  of  transparency  ;  although  its  nature 
is  extremely  dense,  and  it  possesses  extra- 
ordinary toughness  and  tenacity.  Veteri- 
nary writers  and  lecturers  have  endowed 
the  laminae  with  a  high  degree  of  elasticity : 
but  it  appears  to  me  that  the  property 
is  referable  to  their  connections,  and  not 
one  that  is  inherent  in  their  own  sub- 
stance. 

"  Elastic  Structure.  —  This  is  a  substra- 
tum of  a  fibrous  periosteum-like  texture, 
attaching  the  laminae  to  the  coffin-bone,  in 
which  it  is  that  the  property  of  elasticity 
resides  to  that  remarkable  extent  usually 
ascribed  to  the  laminae  themselves  :  indeed, 
so  elastic  is  it  found  to  be,  that  it  can  be 
made  to  stretch  and  recede  the  same  as  a 
piece  of  India  rubber.  Its  fibres  take  a 
direction  downward  and  backward.  At 
the  same  time,  it  affords  a  commodious  bed 
for  the  ramification  of  blood-vessels  issuing 
from  the  substance  of  the  bone,  in  which 
they  are  (particularly  in  the  stretched  con- 
dition of  the  substance)  protected  from  in- 
jurious compression  and  consequent  inter- 
ruption to  their  circulation. 

"  Number.  —  In  round  numbers  we  may 
estimate  the  laminae  at  about  500 ;  not  in- 


THE   HORSE. 


33 


eluding  those  of  the  bars.  They  vary, 
however,  in  number :  I  have  reckoned  up- 
wards of  600. 

"  Dimensions.  —  In  length  they  decrease 
from  around  the  toe  towards  the  sides  and 
heels  in  a  corresponding  ratio  with  the 
wall  ;  those  in  front,  the  longest,  being 
rather  more  than  two  inches  in  extent ;  the? 
shortest,  those  at  the  heels,  being  rather  less 
than  one  inch.  In  breadth  there  is  no  vari- 
ation :  all  measure  alike,  one-tenth  of  an 
inch. 

"  Organization.  —  The  laminae  are  highly 
organized,  though  they  are  not  equally  so 
with  either  the  sensitive  sole  or  sensitive 
frog;  nor  are  they  so  red  as  those  parts: 
and  the  obvious  explanation  of  this  is, 
that  (over  and  above  what  is  requisite  for 
their  own  nutrition)  all  the  blood  they  have 
occasion  for  is  only  that  which  is  suffi- 
cient for  the  secretion  of  the  horny  la- 
minjE. 

"  THE    SENSITIVE    SOLE. 

"  The  sensitive  sole,  or  (as  Sainbel  calls 
it)  the  fleshy  sole,  is  the  fibro-vascular  sub- 
stance covering  the  arched  concave,  or 
ground  surface,  of  the  coffin-bone  ;  in  fact, 
is  the  part  corresponding  to  the  horny  sole. 

"  Structure.  —  The  same  kind  of  elastic 
fibrous  structure  that  sustains  the  laminae 
is  found  constituting  the  groundwork  of  the 
sensitive  sole ;  only  that  in  the  latter  case  it 
is  closer,  denser,  and  firmer  in  its  texture. 
Upon  this  is  spread  a  remarkably  beautiful 
venous  network.  And  the  whole  is  en- 
veloped in  an  outer  cuticular  covering, 
derived  from  the  heels  and  frog,  from  which 
are  sent  villous  processes,  loaded  with  the 
points  of  arteries  into  the  porosities  of  the 
horny  sole:  not,  however,  perpendicularly 
downward,  but  in  an  oblique  direction  — 
downward  and  forward  —  the  same  in 
which  the  horny  fibres  grow. 

"  Connection.  —  Around  the  circumfer- 
ence of  the  coffin-bone,  the  sensitive  sole 
is  connected  with  the  fibrous  substance  de- 
scending from  the  wall,  together  with  the 
tapering,  vanishing  points  of  the  laminae. 
In  the  centre,  it  is  united  with  the  bars  and 


frog.  But  its  principal  attachment  consists 
in  its  being  firmly  rooted  into  the  sole  of 
the  coffin-bone ;  a  connection  that  receives 
considerable  addition  from  the  blood-vessels 
issuing  out  of  the  substance  of  the  bone. 

"  Thickness. —  The  sensitive  sole  varies 
in  thickness  at  different  places.  On  an 
average,  it  may  be  said  to  measure  one- 
eighth  of  an  inch  in  thickness.  In  the  vi- 
cinity of  the  frog,  it  is  something  less  than 
this.  At  the  heels,  it  possesses  double  that 
thickness. 

"  Organization.  —  This  is  one  of  the 
most  vascular  and  sensitive  parts  in  the 
body.  Independently  of  the  much  ad- 
mired venous  network  expanded  over  the 
fibrous  substance  of  the  sole,  arteries  enter 
it  issuing  from  the  substance  of  the  bone, 
and  penetrate  its  villi,  w^hich,  by  taking  this 
course,  elude  all  compression  and  obstruc- 
tion :  there  are  also  others  —  the  nutrient 
arteries ;  but  these  have  an  external  origin, 
from  the  inferior  coronary  artery.  The 
chief  assemblage  of  arteries  takes  place 
within  the  villi,  upon  the  cuticular  surface 
—  those  issuing  out  of  the  interior  of  the 
bone  simply  passing  through  (without  ram- 
ifying within)  the  fibrous  substance :  so 
that,  if  the  substance  of  the  sole  is  laid 
open  by  transverse  section,  th^  incised 
edge,  near  the  surface,  exhibits  a  deep  red 
tint ;  while  the  interior,  nearer  the  bone, 
has  a  pinkish  or  pale  red  aspect. 

"  THE    SENSITIVE    FROG. 

"  Under  this  head  is  included  the  cleft, 
cuneiform  body,  projecting  from  the  bottom 
of  the  foot,  together  with  the  substance 
continued  from  it  and  filling  the  interval 
between  the  cartilages.  Sainbel  calls  it 
'  the  fleshy  frog.' 

"  Division.  —  We  distinguish,  in  the 
sensitive  as  in  the  horny  frog,  an  apex  or 
toe ;  two  heels,  separated  by  the  cleft ;  and 
a  portion  intermediate  between  these,  which 
is  the  body. 

"  Situation  and  Connection.  —  The  sensi- 
tive frog  occupies  the  posterior  and  central 
parts  of  the  bottom  of  the  foot,  forming  in 
the  tread  a  firm  and  secure  point  d^appui. 


34 


ANATOMY   AND   PHYSIOLOGY   OF   THE   HORSE. 


Being  in  the  hoofloss  foot  equally  promi- 
nent with  the  projecting  edge  of  the  coffin- 
bone,  one  might  be  led  to  infer  that  the 
horny  frog  should  take  the  same  line  of 
bearing  with  the  crust.  The  frog,  alto- 
gether, is  lodged  in  a  capacious  irregular 
space,  bounded  superiorly  by  the  tendo- 
perforans  and  common  skin,  laterally  by  the 
cartilages,  and  inferiorly  by  the  horny  frog : 
with  all  which  parts  it  has  connections ; 
besides  being  continuous  with  the  sensitive 
bars  and  sole,  and  at  the  heels  with  the 
coronary  substance.  On  its  sides  are  two 
shallow,  ill-defined  hollows,  corresponding 
to  the  commissures  of  the  horny  frog,  into 
which  are  received  the  horny  prominences 
opposed  to  them. 

"  Structure.  —  Entering  into  the  com- 
position of  this  body  we  distinguish  four 
parts :  An  exterior  or  cuticular  covering ; 
a  congeries  or  network  of  blood-vessels ;  a 
fibro-cartilaginous  texture ;  and  an  elastic 
interstitial  matter. 

"  The  exterior  or  cuticular  covering  in- 
vests the  prominent  bulbous  portion  of  the 
frog,  and  also  gives  a  lining  to  the  cleft. 
Superiorly,  it  is  continuous  with  the  skin 
descending  upon  the  heels  ;  anteriorly,  with 
the  cuticular  covering  of  the  coronet ;  infe- 
riorly, with  that  of  the  sole.  Numerous 
villous  processes  sprout  from  its  surface, 
and  enter  the  porosities  in  the  interior  of 
the  horny  frog,  taking  a  direction  down- 
ward and  forward,  the  same  as  that  in 
which  the  fibres  of  the  horn  grow. 


"  The  vascular  covering  succeeds  the 
cuticular,  lying  immediately  underneath  it. 
It  consists  of  a  network  of  blood-vessels, 
principally  veins,  but  which  are  not  so 
thickly  set  as  upon  the  sole. 

"  The  fibro-cartilaginous  case  comes  next. 
We  find  it  spread  over  those  parts  most 
subjected  to  pressure,  and  to  be,  in  many 
places,  one-fourth  of  an  inch  in  thickness. 
From  its  interior  are  sent'  off  numerous 
processes,  pervading  the  elastic  matter  of 
the  frog,  forming  so  many  septa  intercross- 
ing one  another,  and  dividing  it  without  any 
notable  regularity  into  many  unequal  com- 
partments. In  the  posterior  and  bulbous 
parts,  the  septa  exist  in  greater  numbers, 
and  are  closer  arranged  than  in  the  middle 
parts.  The  fibres  of  this  vaginal  substance 
run  obliquely  downward  and  forward,  and 
become  intermixed  around  the  borders  with 
those  of  the  bars  and  sole. 

"  The  elastic  interstitial  matter^  however, 
composes  the  bulk  of  the  sensitive  frog. 
It  consists  of  a  pale  yellowish  soft  sub- 
stance, which  has  been  mistaken  for  fat  or 
oil,  and  hence  has  been  named  '  the  fatty 
frog.'  When  cut  deeply  into,  it  exhibits  a 
granulated  appearance,  and  the  fibrous  in- 
tersecting chords  become  apparent,  putting 
on  the  ramous  arrangement  of  a  shrub  or 
tree.  Altogether,  the  sensitive  frog  forms 
a  peculiar,  spongy,  elastic  body,  for  which 
we  lack  some  more  appropriate  name." 


A  TABULAR  VIEW  OF  THE  BONES  OE  THE  HORSE. 


BONES  OF  THE  CRANIUM. 

Number. 

Frontal, 1 

Parietal, 2 

Temporal,  two  pairs, 4 

Occipital, 1 

Ethmoid, 1 

Sphenoid, 1 

BONES  OF  THE  FACE. 

Nasal, 2 

Superior  and  anterior  maxillarj',       .        .  4 

Malar, 2 

Lacrymal,        ......  2 

Palatine, 2 

Superior  and  inferior  turbinated,     .         .  4 

Vomer, 1 

Lowerjaw, 1 

TEETH. 

Incisors, 12 

Canine, 4 

Molars, 24 

BONE  OF  THE  TONGUE. 

Os  Hyoideus, 1 

BONES  OF  THE  EAR. 

Malleus, 2 

Incus 2 

Stapes, 2 

Orbiculare, 2 

BONES  OF  THE  SPINE. 

Cervical, 7 

Dorsal, 18 

Limibar  (sometimes  G  are  found),  .        .      5 

BONES  OF  THE  SACRUM  ANTD  TAHi. 

Sacral, 1 

Coccygeal  (tail),  about         .         .         .        .15 

BONES  OF  THE  CHEST. 

Eibs,  on  each  side  18,      .        .        .        .  36 

Sternum,    ....  .        .  1 

PELVIS. 

Innominata  (or  bones  without  a  name),     .  2 

BONES  OF  THE  SHOULDER. 

Scapular,    .        .  ....  2 


BONES  OF  THE  ARM. 
Humeral, 2 

BONES  OF  THE  FORE-ARM. 

Radial  and  ulnar.  The  ulnar  being,  m  the 
adults,  connected  with  the  radius,  we  shall  con- 
sider them  as  one  bone.     Kadial,  .         .         2 

BONES  OF  THE  EINEE. 

The  carpal  bones  are  thus  named  : 

^  f  Scaphoid,  |    f  Pisiform, 

(§  J  Lunar,  «  J  Trapezoid, 

"S  I  Cuneiform,  g  1  Magnum, 

S  1^  Trapezium.  J   [  Unciform. 

Eight  bones  to  each  knee,  ...         16 

BONES  BELOW  THE  KNEE. 

Metacarpal, 2 

Splents, 4 

Pastern,      .......  2 

Coronet, 2 

Sessamoid, 4 

Navicular, 2 

Pedal  or  foot  bones, 2 

BONES  OF  THE  HIND  EXTREMITY. 

Femur, 2 

Stifle, '    .         .  2 

BONES  OF  THE  LEG. 

Tibia  and  fibula.  These  we  shall  consider  as 
one  to  each  extremity,         ....  2 

BONES  OF  THE  HOCK. 

Astragalus, 2 

Os  Calcis, 2 

Cuboid, 2 

Cuneiform,       ......  6 

BONES  OF  THE  LEG. 

Two  cannons  and  four  splents,     ...        6 

BONES  BENEATH  THE  CANNON. 

Pastern, 2 

Coronet, 2 

Sessamoids, 4 

Navicular, 2 

Pedal  or  foot  bones,        ....  2 

Total  number  of  bones,         .         .         238 
The   correct  technical  nomenclature   of  the   above 
bones  wiU  be  found  in  "  Osteology,"  which  see. 

(35) 


ANATOMY  OF  THE  SKELETON. -OSTEOLOGY. 


OSSEOUS  SYSTEM  OF  THE 
HORSE. 

In  the  form  of  answers  to  a  series  of 
questions,  the  student  will  become  ac- 
quainted with  the  name,  location,  form,  use, 
and  general  peculiarities  of  the  various 
bones  composing  the  horse's  skeleton. 

Q.  What  is  understood  by  the  7iatural 
skeleton  ?  —  A.  The  term  is  applied  when 
the  whole  bones  are  held  together  by  their 
natural  attachments  :  ligaments,  cartilages, 
and  synovial  membranes. 

Q.  Why  is  the  term,  artificial,  sometimes 
applied  to  the  skeleton  ?  —  A.  Because  the 
bones,  having  been  divested,  by  maceration 
or  otherwise,  of  their  connecting  ligaments, 
etc.,  are  united  artificially.)  by  wire  and 
plates  of  metal. 

BONES    OF    THE    CRANIUM. 

Q.  Enumerate  the  cranial  bones.  —  A. 
Frontal,  two  parietal,  occipital,  four  tempo- 
ral, ethmoid,  sphenoid :   ten. 

FRONTAL    BONE    (oS    FRONTIs). 

Q.  Describe  the  situation  of  the  frontal 
bone.  —  A.  It  occupies  the  antero-superior 
part  of  the  cranium  in  the  region  known  as 
the  forehead. 

Q.  What  are  its  peculiarities  ?  —  A.  In 
form  it  is  irregular,  having  two  surfaces 
and  four  borders.  Its  surfaces  are  flat 
externally,  concave  internally.  Its  internal 
surface  is  divided  by  a  septum  into  anterior 
and  posterior  concavities.  The  posterior 
one  is  occupied  by  a  portion  of  the  anterior 
lobe  of  the  cerebrum ;  the  anterior  consti- 
tutes the  frontal  sinuses,  they  being  sepa- 
rated from  each  other  by  the  nasal  spine. 
The  concavity  is  further  divided  into  shal- 
low chambers  by  imperfect  septa. 


Q.  Describe  the  borders  of  the  os  frontis. 
—  A.  They  are  denticulated  and  squamous. 
The  posterior  is  arched,  describing  segments 
of  two  circles.  The  anterior  or  nasal  is 
waving,  inclines  backwards  and  outwards. 
The  frontal  border  is  straight,  anteriorly 
broad  and  triangular.  The  ethmoidal  or 
outer  border  is  irregular,  and  unites  with 
the  lachrymal,  sphenoid,  and  ethmoid  bones. 

PARIETAL  BONES  (oSSA  PARIETALa). 

Supposing  the  horse  to  be  an  adult,  we 
shall  consider  these  bones  as  one. 

Q.  What  is  the  situation  of  the  parietal 
bone  ?  —  A.  It  occupies  the  mesio-superior 
part  of  the  cranium. 

Q.  Describe  the  same.  —  A.  Its  form  is 
quadrilateral :  vaulted,  concave  internally, 
and  convex  externally.  It  has  two  sur- 
faces and  four  borders,  denticulated  and 
squamous. 

Q.  What  is  observable  on  the  convex  sur- 
face ?  —  A.  A.  longitudinal  messian  crest, 
bifurcating  anteriorly  ;  which  indicates  the 
location  of  the  sutures,  now  obliterated  by 
age.  Between  the  bifurcatures  arises  an 
eminence  above  the  cranial  surface. 

Q.  Describe  the  appearance  of  the  inter- 
nal surface?  —  A.  It  is  indented  by,  and 
receives,  the  lobular  eminences  of  the  cere- 
brum, and  it  is  also  furrowed  by  arterial 
ramifications  which  supply  the  dura  mater. 

temporal  BONES  (oSSA  TEMPORUm). 

Q.  What  portion  of  the  cranium  do  the 
ossa  temporum  occupy  ?  —  A.  Its  sides  and 
base. 

Q.  How  do  these  bones  differ  from  those 
in  man  ?  —  A.  In  man  they  are  divided  into 
three  portions,  squamous,  petrous,  mastoid; 
yet  in  reality  they  are  united.     In  the  horse 

(36) 


ANATOMY.  AND  i' PHYSIOLOGY   OF  •  THE  .HORSE. 


37 


they  constitute  four  distinct  bones,  two  on 
each  side. 

Q.  Name  them.  —  A.  Two  ossa  tempo- 
rum,  pars  squamosa,  pars  petrosa :  four. 

Q.  Describe  their  appearance.  —  One 
pair  is  composed  of  laminas,  vaulted ;  form 
ovoid,  surmounted  by  irregular  projections ; 
the  other  pair  are  solid  and  convex. 

OCCIPITAL    BONE    (oS    OCCIPITEs). 

Q.  What  is  the  situation  of  the  os  occi- 
pites?  —  A.  It  is  located  in  the  postero- 
superior  and  inferior  parts  of  the  cranium. 

Q.  What  is  its  form  ?  —  A.  Convex 
externally,  irregular,  having  an  occipital 
tuberosity  and  condyles. 

Q.  What  are  the  connections  of  this 
bone  ?  —  A.  It  unites,  superiorly,  with  the 
parietal  bones ;  inferiorly  and  anteriorly  with 
the  sphenoid ;  laterally,  with  the  temporal, 
and  it  articulates  posteriorly  with  the  atlas. 

Q.  What  is  the  foetal  state  of  the  bone  ? 
A.  It  is  easily  separable  into  four  portions. 

Q.  State  its  use.  —  A.  It  forms  the  pos- 
terior and  inferior  parts  of  the  cranium, 
protects  this  portion  of  the  brain,  and  gives 
exit  to  the  spinal  cord. 

SPHENOID    BONE    (oS    SPHENOIDES). 

Q.  What  is  the  situation  of  the  os 
sphenoides  ?  —  A.  It  passes  from  one  tem- 
poral region  to  the  other,  across  the  antero- 
inferior part  of  the  brain. 

Q.  What  are  its  general  divisions?  —  A. 
It  is  divided  into  body,  situated  in  the  mid- 
dle, alaB  or  wings,  on  each  side,  and  two 
pterygoid  processes,  considered  as  legs. 

Q.  To  what  bones  is  it  connected  ? — A. 
Occipital,  ethmoid,  squamous-temporal,  pal- 
ate, and  vomer. 

ETHMOID    BONE  (oS    ^THMOIDES). 

Q.  What  part  of  the  cranium  does  the 
OS  aethmoides  occupy  ?  —  A.  Anterior  to 
the  sphenoid,  and  is  the  boundary  of  the 
cranial,  and  commencement  of  the  nasal, 
cavities. 

Q.  Describe  its  form.  — ^.  The  posterior 
portion  bears  resemblance  to  a  bird  with  its 
wings  extended,  having  no  legs,  but  a  long 


erected  neck  and  a  smaU  round  head ;  the 
anterior  part  consists  of  a  slim,  brittle, 
porous,  spongy  structure  of  considerable 
volume. 

Q.  What  are  its  connections?  —  A. 
With  ,the  sphenoid,  frontal,  vomer,  and 
superior  turbenated  bones;  and  with  the 
cartilaginous  septum  of  the  nose. 

BONES    OP    THE    FACE. 

Under  this  head  we  shall  consider  the 


Ossa  nasi, 

"      maxillaria  superiora, 

"      maxillaria  anteriora, 

"      malarum, 

"      lacrymalia, 

"      palati, 

"      tm-binati,  superior  et  inferiora, 

"      vomer,       .... 
Os  maxillare  inferus,  (lower  j  aw,) 


Total, 18 

We  shall  now  consider  these  bones  in  the 
above  order. 

NASAL    BONES    (oSSA    NASi). 

Q.  How  many  nasal  bones  are  there  ? — 
A.    Two. 

Q.  Where  are  they  situated?  —  A.  In 
the  superior  part  of  the  face. 

Q.  Describe  their  form? — A.  They  re- 
semble the  form  of  a  pear ;  are  broad  pos- 
teriorly, pointed  anteriorly ;  they  are  convex 
externally  and  concave  internally. 

Q.  To  what  bones  are  they  connected  ? 
— -A.  To  the  frontal,  superior  and  anterior 
maxillaria,  and  lachrymal. 

Q.  What  is  theuruse?— A  To  defend 
the  nares,  and  retain  in  position  the  septura 
nasi. 

SUPERIOR  MAXILLARY  BONES  (oSSA  MAXIL- 
LARIA superiora). 

Q.  Where  are  they  situated? — A.  In 
the  supero-lateral  parts  of  the  face. 

Q.  Describe  their  form  ?  —  A.  They  are 
somewhat  irregular — trilateral;  from  the 
centre  (which  is  thickest)  they  taper,  the 
anterior  part  being  much  thinner  than  the 
posterior. 

Q.    How  are  they  divided? — A.   Each 


38 


ANATOMY   AND   PHYSIOLOGY  OP 


bone  has  a  facial,  palatine,  and  nasal  sur- 
face. It  has  also  nasal,  alveolar,  and  pala- 
tine borders,  and  two  extremities  :  posterior, 
which  forms  the  maxillary  tuberosity  ; 
anterior,  or  dental  extremity. 

Q.  "What  are  the  connections  of  the  ossa 
maxilaria  ?  —  A.  With  the  squamous  tem- 
poral, nasal,  anterior  maxillary,  malar, 
laclirymal,  palate,  and  inferior  turbinated 
bones. 

ANTERIOR    MAXILLARY    BONES     (oSSA    MAXIL- 
LARIA    ANTERIORa). 

Q.  What  is  the  situation  of  these  bones? 
—  A.  They  are  placed  in  the  supero-anterior 
and  antero-lateral  parts  of  the  face. 

Q.  What  is  the  general  form  of  these 
bones  ?  —  A.  Very  irregular ;  consisting  of 
a  broad,  thick  base,  turned  forwards,  from 
which  is  sent  off  a  thin  flexible  plate  ;  and 
a  narrow,  elongated,  tapering  portion 
turned  backwards. 

Q.  How  is  each  bone  divided  ?  —  A.  Into 
three  surfaces  and  three  borders. 

Q.  Describe  the  surfaces.  —  A.  The 
superior  or  nasal  surface  is  smooth,  con- 
vex, and  oblong.  The  inferior  or  palatine 
is  vaulted,  it  contributing  to  the  formation 
of  the  palate ;  within  it,  of  an  oval  form,  is 
the  interdental  space,  which  is  occupied  by 
two  thin,  flexible  plates,  the  palatine  pro- 
cesses, denticulating  along  the  sides  with 
each  other.  In  the  side  of  the  bone  is  a 
deep  hollow,  for  the  reception  of  that  por- 
tion of  the  superior  maxillary  bone  which 
holds  the  tusk ;  and  the  remainder  of  the 
surface,  posteriorly,  is  articulated  with  the 
same.  The  anterior  or  labial  surface  is 
broad,  smooth,  and  convex,  and  gives  at- 
tachment to  the  depressor  labii  superioris, 
and  gums. 

Q.  Describe  the  borders.  —  A.  The 
anterior  border  is  broad  and  curved,  and  is 
composed  of  two  laminae,  formed  apart  and 
divided  into  septa  for  the  insertion  of  six 
incisors.  The  posterior  border  is  narrow 
and  sloped,  and  denticulates  with  the  nasal 
bone.  The  internal  border  is  broad, 
quadrilateral,  curved,  and  denticulates  with 
its    fellow,   forming    thereby   the  superior 


maxillary  symphysis,  through  which  runs 
the  foramen  incisivum,  for  the  transmission 
of  the  palatine  arteries. 

Q.  How  is  this  bone  connected? — A. 
It  connects  with  the  superior  maxillary  and 
nasal  bones,  and  with  its  fellow. 

MALAR    BONES    (oSSA    MALARUM). 

Q.  What  is  the  situation  of  the  ossa 
malarum? — A.  They  occupy  the  antero- 
external  part  of  the  orbit. 

Q.  Describe  their  form.  —  A.  Irregularly 
triangular,  presenting  a  broad  basis  forwards. 

Q.  How  is  the  bone  divided  ?  —  A.  Into 
three  surfaces,  three  angles,  a  basiform  and 
an  apiform  extremity. 

Q.  Name  the  surfaces.  —  A.  Facial, 
maxillary,  and  orbital. 

Q.  Describe  the  same.  —  A.  The  facial 
surface  is  divided  into  two  portions  by  the 
zygomatic  spine  ;  the  upper  division  is 
smooth  and  nearly  flat;  the  lower  part  is 
narrow  and  roughened,  for  the  insertion  of 
the  masseter  muscle.  From  this  surface, 
posteriorly,  arises  the  zygomatic  process, 
which  is  very  obliquely  sloped  off,  and 
laminated  for  adaptation  to  the  process 
of  the  same  name,  meeting  it  from  the  tem- 
poral bone,  the  two  together  forming  the 
zygomatic  arch.  The  maxillary  surface  is 
concave.  The  orbital  surface  has  a  smooth 
concavity  which  forms  the  infero-external 
part  of  the  orbit. 

Q.  Describe  the  angles.  —  A.  There  are 
three,  superior,  inferior,  and  posterior.  The 
superior  constitutes  the  external  portion  of 
the  orbital  circumference.  The  inferior 
forms  the  zygomatic  spine.  The  posterior 
is  not  so  prominent  nor  defined,  but  forms 
an  irregular  link  with  the  superior  maxillary 
bone. 

Q.  What  of  the  extremities  ?— ^1.  The 
anterior  extremity  is  broad,  irregular,  and 
denticulated,  and  articulates  with  the  supe- 
rior maxillary  and  lachrymal  bones.  The 
posterior  or  apiform  extremity  forms  the 
zygomatic  process. 

Q.  With  what  bones  do  the  ossa  mala- 
rum connect  ?  —  A.  With  the  temporal, 
superior,  maxillary,  and  lachrymal  bones. 


THE  HORSE. 


39 


LACHRYMAL  BONES  (oSSA  LACHRYMALIa). 

There  are  two  lachmyral  bones:  we  shall 
describe  but  one,  considering  that  they  are 
both  alike,  as  indeed  are  those  already  refer- 
red to,  in  a  plural  sense. 

Q.  What  is  the  situation  of  the  lachry- 
mal bone  ?  —  A.  It  occupies  the  antero- 
external  part  of  the  orbit. 

Q.  How  is  it  divided  ?  —  A.  Into  three 
surfaces  and  five  borders. 

Q.  Name  the  surfaces.  —  A.  Internal, 
external,  and  orbital. 

Q.  Name  the  borders.  —  A.  External 
and  internal  facial,  nasal,  and  external  and 
internal  orbital. 

Q.  What  is  observable  in  the  orbital  ex- 
cavation of  this  bone  ?  —  A.  The  lachrymal 
fossa. 

Q.  What  occupies  this  fossa  or  groove  ? — 
A.  The  lachrymal  vessels,  sac,  and  duct. 

Q.  With  what  bones  is  it  connected  ?  — 
A.  With  the  frontal,  nasal,  malar,  and  supe- 
rior maxillary  bones. 

palate  bones  (ossa  palati). 

Q.  What  is  the  situation  of  the  palate 
bones  ?  —  A.  They  are  placed  in  the  infe- 
rior posterior  part  of  the  face,  adjoining  the 
base  of  the  cranium. 

Q.  What  does  the  palatine  surface  form  ? 
—  A.  The  palatine  arch  or  roof  of  the 
mouth. 

Q.  What  of  the  nasal  surface  ?  —  A.  It 
forms  the  posterior  surface  of  the  nasal 
outlet. 

Q.  What  other  surfaces  do  these  bones 
present  ?  —  A.  Ethmoidal  and  orbital. 

Q.  To  what  part  of  the  bone  is  the  vel- 
lum palatei  attached  ?  — A.  To  the  palatine. 

Q.  How  are  the  palate  bones  united  to 
the  superior  maxillary? — A.  By  their  supero 
and  infero  lateral  borders ;  each  being  den- 
ticulated. 

Q.  What  other  connections  have  the  pal- 
ate bones?  —  A.  They  are  joined  to  the 
frontal,  ethmoid,  sphenoid,  vomer,  and  in- 
ferior turbinated  bones. 

turbinated  bones  (ossa  turbinata  supe- 

RIORA  ET  INFERIORa). 

Q.  Where  are  the  ossa  turbinata  located  ? 


—  A.  Within  the  nasal  cavity :  the  superior 
above,  and  the  inferior  below. 

Q.  What  is  their  form,  and  how  are  they 
divided  ?  —  A.  In  form  they  are  oblong,  thin, 
foliated,  convoluted,  scroll-like,  and  cavern- 
ous. They  are  divided  into  external  and 
internal  surfaces ;  superior  and  inferior  ex- 
tremities. 

Q.  How  many  bones  are  there?  —  A. 
Four. 

Q.  Describe  the  bones.  —  A.  Their  ex- 
ternal surface  is  convex,  and  presents  series 
of  longitudinal  grooves  which  mark  the 
ramifications  of  small  blood-vessels.  The 
internal  surface  is  cellular,  being  unequally 
divided  by  transverse  septa.  Then-  interior 
is  capacious ;  they  are  open  superiorly  and 
closed  anteriorly.  They  are  porous  and 
elastic.  The  superior  bone  exceeds  in 
volume  the  inferior,  and  makes  its  convolu- 
tion from  below,  its  superior  border  being 
attached ;  whereas,  the  reverse  is  the  case 
with  the  inferior  one. 

Q.  What  are  their  connections  ?  —  A. 
The  turbinated  bone  is  connected  above  with 
the  ethmoid ;  and  laterally,  with  the  nasal 
bone. 

VOMER. 

Q.  From  what  does  the  name  of  this 
bone  arise  ?  —  A.  From  its  resemblance  to 
a  ploughshare. 

Q.  What  are  its  uses  ?  —  To  divide  the 
nasal  chambers  and  permit  the  expansion 
of  olfactory  nerves. 

Q.  What  is  inserted  into  its  superior 
groove  ?  —  A.  The  septum  narium. 

Q.  What  are  its  connections  ?  —  A.  It 
unites  with  the  ethmoid,  sphenoid,  superior 
and  anterior  maxillary,  and  palate  bones. 

lower   jaw. INFERIOR     MAXILLARY     BONE 

(os  maxillare  inferius). 

Q.  What  is  the  situation  of  this  bone  ?  — 
A.  It  composes  the  inferior  and  posterior 
parts  of  the  face. 

Q.  What  is  the  foetal  state  of  the  bone  ? 

—  A.  In  the  foetal  state  it  is  divided,  at  its 
inferior  junction,  by  a  connecting  cartilage, 
hence  the  part  has  been  called  its  symphysis. 

Q.  How  is  the  bone  divided  ?  —  A.  Into 


40 


ANATOMY,  AND   PHYSIOLOGY   OF 


body,  neck,  sides,  and  branches ;  external 
and  internal  surfaces,  and  corresponding 
borders. 

Q.  What  do  you  understand  by  these 
terms  ?  —  A.  Body  signifies  the  anterior 
part  reaching  posterior  to  the  tusks ;  neck 
signifies  the  contracted  part,  immediately 
posterior  to  the  body;  sides  are  the  parts 
comprehended  between  the  neck  and  the 
branches ;  the  branches  are  the  parts  poste- 
rior to  the  neck,  which  terminate  in  the  con- 
dyles. As  regards  surfaces.)  the  external  is 
convex,  rounded,  rough,  and  porous,  and 
affords  attachment  for  muscle  and  gum. 
The  internal  surface  is  concave,  rough,  and 
porous,  and  answers  for  the  attachment  of 
muscles  and  gum,  and  as  a  channel  for  the 
tongue,  and  attachment  for  the  fioenum 
linguas. 

Q.  What  do  you  understand  by  borders  ? 
—  A.  Each  superior  border  exhibits  six 
alveolar  cavities  for  the  molar  teeth ;  the 
septum  are  composed  of  osseous  laminae. 
The  inferior  border  is  thin  and  irregular. 
The  posterior  border  is  broad  and  roughened 
for  the  insertion  of  muscles. 

GENERAL    INQUIRIES. 

It  is  now  presumed  that  we  understand 
the  location  and  names  of  the  different  bones 
composing  the  cranium  and  face;  and,  be- 
fore we  proceed  further,  it  may  be  profitable 
to  make  some  general  inquiries  regarding 
the  bony  structure. 

Q.  Is  not  the  number  of  bones  greater 
during  colthood  than  at  mature  life  ?  —  A. 
Yes,  many  of  the  bones  separable  at  that 
period  become  united  in  the  adult. 

Q.  How  are  bones  divided  ?  —  A.  They 
are  divided  into  long  or  cylindrical,  broad 
or  flat,  and  thick. 

Q.  What  do  you  understand  by  epiphy- 
sisis  of  bones?  —  A.  The  region  where  car- 
tilage is  interposed  between  bones  that 
finally  become  ossified. 

Q.  What  is  the  structure  of  bones?  — 
A.  They  consist  of  a  cellular,  reticular,  and 
vascular  parenchyma,  and  of  osseous  mat- 
ter deposited  in  it:  their  base,  therefore, 
is  the  same  as  that  of  the  soft  parts. 


Q.  Are  bones  vascular  ?  —  A.  Yes. 

Q.  How  can  you  demonstrate  their  vas- 
cularity ?  —  A.  By  numerous  small  fora- 
minae  and  by  the  tinge  they  receive  from  the 
coloring  matter  of  the  food. 

Q.  Name  the  investing  membrane  of 
bones  ?  — A.  Periosteum. 

Q.  What  is  its  organization  ?  —  A.  Fi- 
brous. 

Q.  Of  w^hat  use  is  this  periosteum?  — 
A.  It  limits  the  growth  of  bones,  is  the 
medium  of  circulation  and  nutrition,  and 
affords  attachment  for  ligaments  and  mus- 
cles, and  favors  the  free  articulation  of  the 
latter. 

Q.  What  does  its  internal  surface  se- 
crete ?  —  A.  An  oleaginous  fluid,  depos- 
ited in  the  cellular  structure  and  cavity  of 
bones. 

Q.  What  are  foramina?  —  A.  Holes 
perforating  the  substance  of  bones. 

Q.  What  are  sinuses  ?  —  A.  Occurring 
in  bones,  they  are  large  cavities  with  small 
openings. 

Q.  What  are  sinuosities  ?  —  A.  Superfi- 
cial but  broad  irregular  depressions. 

Q.  What  are  furrows  ?  —  A.  Long,  nar- 
row, and  superficial  canals. 

Q.  What  are  notches  ?  —  A.  Cavities  in 
the  margin  of  bones. 

Q.  What  are  fossas  ?  —  A.  Deep  and 
large  cavities  on  the  surface  of  bones. 

Q.  What  are  glenoid  cavities? — A. 
Cavities  for  articulation. 

Q.  What  are  tubercles  ? — A.  Small  em- 
inences. 

Q.  What  are  tuberosities  ?  —  A.  Rough 
elevations. 

Q.  What  are  spines  ?  —  A.  Long  pro- 
jections upon  a  bone. 

Q.  What  are  heads?  —  A.  The  round 
tops  of  bones. 

Q.  What  are  necks  ?  —  The  narrow  por- 
tion of  bones  beneath  their  heads. 

Q.  What  are  processes  ?  —  A.  Short  pro- 
jecting portions  of  bones. 

THE  TRUNK (REMARKS  ON  THE  SAMe). 

We  shall  now  consider  the  peculiarities 
of  the  trunk;  which  comprehends  the  verte- 


EXPLANATIONS   OF  FIGURE  V. 


RIUSCULAR  STRUCTURE. 

LATERAL  VIEW  OF  THE  HEAD,  NECK,  AND  SHOULDEE.  —  THE  HEAD, 


a. 

Orbicularis  palj^ebrarum. 

h. 

Levator  palpebrae. 

c. 

Dilatator  naris  lateralis. 

d. 

"           "     anterior. 

e. 

Orbicularis  oris. 

/• 

Nasalis  longus. 

9- 

Levator  labii  superioris. 

i. 

Zygomaticus. 

3- 

Retractor  labii  inferioris. 

k. 

Buccinator. 

K. 

Masseter. 

I.  . 

Temporalis. 

m. 

Attolentes  et  abducens  aurem. 

/• 

Facial  veins. 

THE  NECK. 

« 

Ligamentum  colli. 

6". 

Rhomboideus  longus. 

s. 

A  portion  of  the  splenius. 

e". 

Scalenus. 

e". 

Pectoralis  par\'us. 

0. 

Abducens  vel  deprimens  aurem. 

r. 

Tendon  of  the  splenius  and  complexus 

major. 

t. 

ObHquus  capitis  inferiorus. 

u. 

Levator  humeri. 

V. 

Sterno  maxillaris. 

X. 

Subscapulo  hyoideus. 

3. 

Jugular  vein. 

EEGION  OF  THE  SHOULDER. 

a".  Trapezius. 
f".  Antea  spinatus. 
g".  Postea  spinatus. 
Ji".  Teres  major. 

OSSEOUS  STRUCTURE. 

*.     Ligamenture  colli,  or  subflavium. 

1.  Temporal  bone. 

2.  Parietal  bone. 

4.  Zygomatic  arch. 

5.  Nasal  bone. 

6.  Lachi-jmal  bone. 

7.  Malar. 

8.  Superior  maxilla. 

9.  Anterior  maxiUa. 

10.  Inferior  maxilla. 

b.  The  neck  of  the  same. 

11.  Cervical  vertebrae. 

33.  Scapula. 

34.  Humerus. 

c.  The  incisors. 

h.     The  lining  membrane  of  the  ear. 


THE   HOESE. 


41 


bral  chain,  thorax,  and  pelvis.  It  is  gener- 
ally called  the  spine,  or  back  bone,  and 
extends  from  the  occipital  bone  to  the  sac- 
rum. The  spine  is  divided  into  three 
regions,  denominated  cervical,  dorsal,  and 
lumbar.  The  spine,  as  a  whole,  exhibits 
three  surfaces  and  two  extremities.  The 
surfaces  are  named  superior,  inferior,  and 
lateral.  The  superior  sm-face  is  flat  in  the 
region  of  the  neck;  in  the  back  and  loins 
it  offers  a  series  of  projections.  The  infe- 
rior surface  is  more  uniform,  and  the  lateral 
is  very  irregular.  *. 

CERVICAL  VERTEBRA. 

Q.  How  many  cervical  vertebree  are 
there  ?  —  A.  Seven. 

Q.  What  is  the  name  of  the  first  ?  —  A. 
It  is  called  atlas. 

Q.  How  does  it  differ  from  the  rest? — A. 
It  has  no  superior  spinous  process  nor  body ; 
the  vertebral  hole  is  larger  than  in  the 
others,  and  its  transverse  processes  are  very 
broad.  It  has  three  pairs  of  foraminas : 
one  posteriorly,  through  which  run  the  verte- 
bral arteries ;  and  two  anteriorly. 

Q.  What  is  the  name  of  the  second  cer- 
vical vertebra  ?  —  A.  It  is  named  dentata. 

Q.  How  is  it  recognized  from  the  rest  ? 
—  A.  By  its  anterior  projection,  which  in 
the  human  subject  resembles  a  tooth. 

Q.  With  what  does  this  tooth-like  pro- 
cess articulate  ?  —  A.  It  articulates  with 
the  infero-posterior  part  of  the  ring  of  the 
atlas. 

Q.  Describe  the  third,  fourth,  and  fifth 
cervical  vertebrte. —  A.  They  possess  the 
genuine  characters  of  cervical  vertebrce,  and 
closely  resemble  each  other;  the  third,  how- 
ever, has  commonly  a  more  elevated  supe- 
rior spine  than  either  of  the  others,  and  is 
narrower  across  the  mesio-superior  part  of 
the  body  (measuring  from  the  roots  of  the 
articular  processes),  which  dimension  in- 
creases in  the  fourth,  but  is  greatest  in  the 
fifth. 

Q.  What  of  the  sixth  vertebral — A.  It 
has  no  inferior  spine  ;  and  its  transverse  pro- 
cesses are  trifid,  consisting  each  of  three 
eminences. 

6 


Q.  What  of  the  seventh  1—A.  It  is  the 
shortest,  and  in  its  general  conformation  re- 
sembles the  first  dorsal.  Its  body,  pos- 
teriorly, presents  two  semilunar  articulai 
depressions,  constituting  a  part  of  the  socket 
for  the  first  rib. 

DORSAL    VERTEBRA. 

Q.    How  many  dorsal  vertebrse  are  there? 

—  A.   Eighteen. 

Q.  What  is  peculiar  to  the  dorsal  ver- 
tebrae ?  —  A.  They  have  each  a  body,  spinous 
process,  and  transverse  process,  and  are 
generally  distinguished  by  the  length,  form, 
and  direction  of  their  spines. 

Q.  How  is  the  first  dorsal  vertebrce  dis- 
tinguished from  the  rest? — A.  By  the 
sharpness  of  its  spinous,  and  singleness  of 
transverse,  processes,  and  by  the  breadth  of 
its  articulatory  surfaces. 

Q.  How  do  the  articular  depressions  for 
the  insertion  of  the  ribs  differ  in  each  bone? 

—  A.    They  are  less  deeply  marked,  as  we 
proceed  posteriorly. 

Q.  How  are  the  seventeenth  and  eight- 
eenth distinguished  from  the  rest? — A. 
They  have  perfect  articulatory  depressions 
on  the  bodies  for  the  insertion  of  ribs. 

LUMBAR    VERTEBRA. 

Q.  How  many  lumbar  vertebrae  are 
there? — A.    Five. 

Q.  How  are  the  bodies  of  the  lumbar 
vertebrce  distinguished  from  the  dorsal? — 
A.  They  are  larger,  contracted  in  the  centre, 
and  their  edges  are  more  prominent. 

VERTEBRAL    CANAL. 

Q.  What  is  the  form  of  the  vertebral 
canal?  —  A.  In  the  cervical  region  it  is  ca- 
pacious and  semi-oval ;  through  the  dorsal, 
transversely  oval  and  smaller.  In  the  lum- 
bar it  is  semi-circular,  of  less  diameter  than 
the  cervical  and  greater  than  the  dorsal. 

Q.  With  what  does  the  spinal  canal  con- 
nect ?  —  A.  Anteriorly,  with  the  cranial 
cavity ;  posteriorly,  with  the  sacral  canal. 

PELVIS,  SACRUM,  AND    TAIL  BONES. 

We  shall  now  consider  the  posterior 
boundary  of  the  trunk. 


42 


ANATOMY  AND  PHYSIOLOGY  OP 


OS  SACRUM. 

Q.  What  is  the  popular  name  of  this 
bone  ?  —  A.    It  is  called  the  "  r7(mp  bone.'''' 

Q.  Where  is  it  located?  —  A.  At  the 
superior  part  of  the  pelvis,  between  the  ossa 
illia. 

Q.  What  is  the  popular  name  of  the 
ossa  illia  ?  —  A.  They  are  called  the  haunch 
bones. 

Q.  How  many  pieces  enter  into  the  com- 
position of  the  sacral  bone,  in  the  foal? — 
A.    It  is  composed  of  five  pieces. 

Q.  How  are  they  united  ?  —  A.  By  fibro- 
cartilaginous  substance. 

Q.  What  ultimate  change  takes  place  in 
this  substance? — A.  It  becomes  ossified, 
and  hence  the  solid  bone. 

Q.  How  is  the  sacral  bone  divided  ?  —  A 
Into  three  surfaces,  two  borders,  base,  and 
apex. 

Q.  Describe  its  surfaces. —  A.  They  are 
named  superior,  inferior,  and  lateral.  The 
superior  is  convex,  very  irregular;  on  its 
central  line  are  five  eminences,  and  laterally 
are  superficial  grooves  pierced  by  the  four 
sacral  foraminte.  The  inferior  surface  is 
smooth  and  slightly  concave.  The  lateral 
surface  is  thick  anteriorly,  gradually  tapering 
posteriorly ;  they  arc  roughened  for  the  re- 
ception of  the  sacro-iliac  hgament. 

Q.  Describe,  briefly,  the  base  and  apex. 
—  A.  The  base  is  composed  of  a  central  and 
two  lateral  parts.  The  apex  is  oval,  and 
articulates  with  the  anterior  bones  of  the  tail. 

BONES    OF    THE   TAIL    (oSSA    COCCYGIs). 

Q.  What  is  the  situation  of  the  ossa 
coccygis  ?  —  A.    Posterior  to  the  sacrum. 

Q.  Of  how  many  bones  is  the  tail  com- 
posed ?  —  A.    Fifteen. 

PELVIS   OR  HAUNCH  BONES  (oSSA  INNOMINATa). 

Q.  How  do  anatomists  divide  these 
bones,  in  the  foetal  state  ?  —  A.  Into  ilium, 
ischium,  and  pubes. 

Q.  In  the  adult  horse  are  there  more 
than  two  bones  ?  —  A.  They  are  considered 
as  two,  yet  in  reality  they  are  united  at  the 
pubes  so  as  to  constitute  but  one  bone.     In 


this  state,  however,  they  are  denominated 
ossa  innominata  —  unnamed  bones. 

Q.  What  is  the  situation  of  the  iliatic, 
ischiatic,  and  pubic  portions? — A.  They 
are  in  the  anterior,  superior,  and  lateral  parts 
of  the  pelvic  region.  The  ischiatic  extends 
posteriorly  and  the  pubic  inferiorly. 

Q.  What  are  the  connections  of  the 
ossa  innominata?  —  A.  They  are  connected, 
anteriorly  and  inferiorly,  to  the  os  sacrum ; 
posteriorly  and  inferiorly,  to  each  other, 
forming  the  symphysis  pubis  ;  laterally, 
with  the  thigh  bones.  * 

Q.  What  are  the  uses  of  the  pelvis? — 
A.  It  affords  an  arch  for  supporting  the 
posterior  parts.  It  contains  the  urinary  or- 
gans, rectum,  etc.,  gives  protection  to  blood- 
vessels and  nerves,  and  origin  and  insertion 
to  various  muscles  and  ligaments. 

CHEST    OR    THORAX. 

The  thorax  or  chest  is  formed  by  the 
dorsal  vertebrae,  superiorly ;  ribs,  laterally ; 
arid  sternum,  inferiorly.  It  also  affords  pro- 
tection to  the  principal  organs  of  circula- 
tion and  respu'ation. 

Q.  State  the  number  of  ribs  and  their 
arrangement? — A.  Their  number  is  gener- 
ally thirty-six ;  eighteen  on  each  side,  eight 
of  which  are  termed  true,  and  the  remainder 
false,  ribs. 

Q.  Why  are  the  anterior  eight  called 
true  ribs  ?  —  A.  Because  they  have  a  direct 
cartilaginous  insertion  into  the  breast  bone 
or  sternum. 

Q.  Why  are  the  posterior  ten  termed 
false  ribs? — A.  Because  they  are  indi- 
rectly  connected  with  the  sternum. 

Q.  What  is  the  general  conformation 
of  a  rib  ?  —  A.  It  is  lengthy,  curved ;  con- 
vex outwardly  or  laterally ;  terminating  in 
a  sharp  border  posteriorly,  which  forms  a 
posterior  convexity.  On  the  inner  surfaces 
it  is  concave,  and  of  course  the  reverse  of 
the  external. 

Q.  What  are  the  variations  in  ribs  ?  — 
A.  They  vary  in  length,  degree  of  curva- 
ture, and  obliquity  of  direction. 

Q.    How  shall  we  divide  each  rib  ?  —  A. 


THE   HOESE. 


43 


Into  a  body,  external  convexity ;  internal 
concavity,  a  superior  and  inferior  termina- 
tion ;  anterior  and  posterior  edges. 

Q.  What  do  you  understand  when  the 
term,  head,  is  applied  to  a  rib  ?  —  A.  It 
signifies  its  protuberance  —  its  superior 
portion;  presenting  a  smooth  convexity  for 
articulation  with  the  bodies  of  vertabree. 

Q.  Where  is  the  neck  of  a  rib  situated  ? 
A.    Immediately  below  the  head. 

Q.  What  is  the  difference  between  the 
anterior  and  posterior  edges  of  the  ribs  ?  — 
A.  The  anterior  edge  is  circular  and  the 
posterior  is  sharp. 

Q.  Where  is  the  tubercle  of  the  rib 
situated  ?  —  A.  Posterior  to  the  head  ;  at 
the  root  of  the  neck. 

Q.  How  is  the  first  rib  distinguished 
from  the  rest  ?  —  A.  It  is  the  shortest  and 
thickest,  and  is  almost  straight. 

Q.  How  does  the  second  rib  differ  from 
the  first  ?  —  A.  It  is  longer,  less  dense, 
and  has  a  greater  curvature  in  the  region  of 
its  neck. 

Q.  How  do  the  ribs  differ  from  the 
second  to  the  seventh  ?  —  A.  They  increase 
in  breadth. 

Q.  How  do  they  differ  in  length  ?  —  A. 
Up  to  the  ninth. 

Q.  How  do  they  differ  in  curvature  ?  — 
A.  Gradually  up  to  the  eighteenth,  which 
is  the  most  curved  of  all. 

BREAST    BONE     (sTERNUM). 

Q.  What  is  the  situation  of  the  sternum? 
—  A.  It  occupies  the  anterior  and  inferior 
portion  of  the  thorax. 

Q.  How  does  it  differ  from  the  human 
sternum  ?  —  A.  In  the  human  subject  it  is 
composed  of  three  pieces ;  in  the  adult 
horse  it  is  considered  as  a  single  bone.  It 
is  made  up,  however,  of  seven  irregularly 
formed  bones. 

Q.  What  is  the  structure  of  the  ster- 
num ?  —  A.  It  is  composed  of  an  osseous 
cellular  substance  and  cartilages. 

Q.  Name  the  cartilages  ?  —  A.  Ensi- 
form  and  cariniform. 

Q.  What  is  the  use  of  the  cariniform 
cartilage  ?  —  A.    It  affords    attachment  to 


the  sterno-maxillares  and  sterno-thyro-hy 
oidei  muscles. 

Q.  To  what  part  of  the  sternum  is  the 
ensiform  cartilage  inserted?  — A.  To  its  in- 
ferior and  posterior  part. 

Having  now  considered  the  bones  of  the 
head  (with  the  exception  of  the  teeth),  and 
hyoides  (appendages),  spine,  thorax,  and 
pelvis,  we  now  commence  on  the  bones 
composing  the  extremities.  These  are  four 
in  number,  disposed  in  pairs,  and  known 
as  the  fore  and  hind  extremities.  Our 
examination  will  be  conducted  with  refer- 
ence only  to  one  fore,  and  one  hind,  ex- 
tremity ;  presuming  that  a  description  of  the 
bones  on  one  side  will  suffice  for  those  on 
the  other. 

FORE   EXTREMITIES. 

Q.  What  is  the  situation  of  the  fore 
extremities  ?  —  A.  They  occupy  the  antero- 
lateral parts  of  the  trunlv,  from  which  they 
proceed  inferiorly. 

Q.  How  are  the  bones  divided  ?  —  A. 
Into  shoulder,  arm,  knee,  leg,  pastern,  coro- 
net, and  foot. 

Q.    Name   the    bones   composing  each 


region 


A. 


SHOULDER    BONES. 

Scapula,  Humerus. 

ARM    BOXES. 

Radius,  Ulnar. 

BOXES  OF  THE  KNEE. 


^  f*  Scaphoid, 
(§  J  Lunar, 
■g  I  Cuneiform, 
tn  l^Trapeziun. 


i  f  Pisiform, 

es  1  Trapezoid, 

1  j  Os  Magnum, 

§  I  Unciform. 

en     N 


BONES   OF   THE  LEG. 

Large  Metacarpal. 
Two  small  Metacarpal  (splents). 

IN  THE  REGION  OF  THE  FETLOCK. 

Two  Sessamoid  Bones. 

PASTERN   BONE. 

Os  SufEi-aginis. 

CORONET  BONE. 

Os  Corona. 

FOO"^  BONES. 

Navicular  and  Coffin-bones. 


44 


ANATOMY   AND   PHYSIOLOGY   OF 


Q,  How  many  bones  compose  one  of 
the  fore  extremities  ?  —  A.    Twenty-one. 

OF    THE    SHOULDER. 

Q.  The  shoulder  being  composed  of  the 
scapula  and  hnnienis,  what  portion  of  the 
thorax  do  they  occupy  ?  —  A.  They  occupy 
its  antero-lateral  region. 

SCAPULA,    (shoulder    BLADe). 

Q.  What  is  the  position  of  the  scap- 
ula ?  —  A.  It  occupies  the  antero-lateral 
parts  of  the  thorax. 

Q.  Describe  the  bone.  —  A.  It  is  trian- 
gular, broad,  and  thin  superiorly ;  narrower 
and  thicker  inferiorly;  its  external  surface 
is  unequally  divided  into  two  superficial 
concavities,  named  fossas  antea  et  postea 
spinatsE.  Its  internal  sm-face  is  smooth,  yet 
excavated. 

Q.  Describe  the  borders.  —  A.  The  su- 
perior has  a  thin,  roughened  summit  for 
the  insertion  of  the  cartilage  of  the  scap- 
ula ;  the  anterior  is  thin  in  its  upper  half, 
yet  below  it  becomes  romided  ;  the  posterior 
is  obtuse  and  rounded. 

Q.  How  does  the  scapula  terminate  in- 
feriorly ?  —  A.   By  a  glenoid  cavity. 

Q.  What  are  the  connections  of  the 
scapula  ?  —  A.  It  has  a  ligamentous  con- 
nection with  the  spines  of  some  of  the  dorsal 
vertebrae ;  to  the  thorax,  it  is  connected  by 
muscular  faschia;  and  its  inferior  connec- 
tion is  by  means  of  the  glenoid  cavity,  to 
the  head  of  the  humerus ;  this  latter  forms 
the  shoulder  joint. 

-Q.  Is  there  anything  remarkable  about 
the  shoulder  joint? —  A.  Its  most  remark- 
able feature  is,  the  great  disproportion  in 
size  between  the  head  of  the  humerus  and 
the  glenoid  cavity. 

Q.  How  is  this  disproportion  in  magni- 
tude compensated  for  ?  —  A.  By  an  exten- 
sive capsular  membrane,  wliich  admits  of 
extensive  motion. 

Q.  What  are  the  insertions  of  this  cap- 
sular membrane?  —  A.  It  has  a  circular 
insertion  into  the  rough  margin  of  the 
glenoid  cavity,  and  also  around  the  neck  of 
the  humerus. 


Q.  How  is  this  membrane  protected  in- 
ternally and  externally  ?  —  A.  Internally  it 
is  clothed  with  a  synovial  membrane ;  ex- 
ternally by  adherent  muscles. 

HUMERUS. 

Q.  What  is  the  situation  of  the 
humerus  ?  —  A.  It  is  situated  beneath  the 
scapula,  occupying  a  diverse  direction,  viz., 
downwards  and  backwards,  and  is  in  con- 
tiguity with  the  lateral  parts  of  the  thorax. 

Q.  Describe  the  form  of  the  humerus. 
—  A.  It  is  irregular,  cylindroid,  having  a 
convoluted  appearance,  and  its  superior 
extremity  is  much  larger  than  the  inferior. 

Q.  How  is  this  bone  divided?  —  A. 
Into  a  body,  superior  and  inferior  extremi- 
ties. 

Q.  Describe  the  bod?/.  —  A.  It  is  angu- 
lar, with  sides,  contracted  superiorly,  and 
flattened  and  rounded  inferiorly.  From  its 
superior-anterior-lateral  margin  projects  a 
roughened  tuberosity,  into  which  the  leva- 
tor humeri  is  inserted.  The  lateral  part  of 
the  body  is  hollow  or  excavated.  The  in- 
ner side  is  somewhat  roughened  and  promi- 
nent. 

Q.  Describe  the  superior  extremity.  — 
A.  The  superior  extremity  being  much 
larger  than  the  inferior,  presents  a  head 
and  several  tubercles  :  it  has  a  projecting, 
hemispherical  surface,  designed  for  exten- 
sive articulation.  It  presents  a  smooth 
surface,  yet  has  an  irregular,  indented 
groove  for  the  insertion  of  a  capsular  liga- 
ment. 

Q.  What  is  the  use  of  the  tubercles  ?  — 
A.  The  anterior,  three  in  number,  serve  as 
articulations  for  the  flexor  brachii  to  tra- 
verse. The  fourth  serves  as  a  protection 
against  dislocation. 

Q.  Describe  the  inferior  extremity.  —  A. 
It  consists  of  two  heads  or  condyles,  sepa- 
rated by  deep  ovoid  fossa,  into  which  is 
received  the  olecranon  of  the  ulna. 

Q.  What  are  the  connections  of  the 
humerus  ?  —  A.  Superiorly,  it  connects 
with  the  scapula ;  inferiorly,  it  articulates 
with  the  radial  and  ulnar  extremity  of  the 
Os  Brachii. 


THE  HORSE, 


45 


OS    BRACHII    (arm    bone). 

Q.  Describe  the  location  of  the  os 
brachii.  —  A.  It  is  located  beneath  the  tho- 
rax, in  the  inferior  region  of  the  humerus. 

Q.  How  does  this  bone  differ  from  those 
of  the  human  subject  ?  —  A.  By  being  con- 
solidated into  a  single  bone. 

Q.  How  is  it  divided  ?  —  A.  Into  radial 
and  ulnar  portions. 

Q.  Describe  the  radial. —  A.  It  consists 
of  a  body,  superior  and  inferior  extremi- 
ties. The  body  is  lengthy,  compared  with 
other  bones  of  the  fore  extremity ;  posteri- 
orly it  is  excavated  and  roughened ;  ante- 
riorly it  projects  with  a  smooth,  cylindrical 
surface. 

Q.  Describe  the  superior  extremity. — 
A.  The  superior  extremity  presents  an  in- 
terrupted articulatory  surface,  having  a 
central  eminence,  with  two  cavities,  which 
correspond  to  the  articulations  of  the  os 
humerii. 

Q.  Describe  the  inferior  extremity.  — 
A.  It  appears  to  consist  of  three  articulatory 
surfaces,  which  correspond  with  those  of  the 
bones  of  the  carpus. 

Q.  Describe  the  ulnar  portion  of  the  os 
brachii.  —  A.  It  presents  a  tapering  trian- 
gular projection,  firmly  connected  with  the 
radius ;  at  its  junction  with  the  same,  it 
presents  a  semilunar  concavity ;  this,  with 
the  articulatory  surface  of  the  radius,  forms 
the  humero-brachial  articulation. 

Q.  Name  the  projection  of  the  ulnar, 
commonly  termed  point  of  the  elbow.  —  A. 
Olecranon. 

Q.  What  muscle  is  inserted  into  the  ole- 
cranon ?  —  A.  The  triceps  extensor  brachii. 

Q.  What  is  the  state  of  this  bone  in 
early  colthood  ?  —  A.  It  is  composed  of  two 
pieces  named  radius  and  ulnar,  which  after- 
wards become  consolidated. 

Q.  With  what  bones  does  the  inferior 
portion  of  the  os  brachii  articulate  ?  —  A. 
With  the  scaphoid,  lunar,  and  cuneiform 
bones. 

BONES    OF    THE    KNEE    (cARPUS). 

The  bones  of  the  knee  correspond  to  the 
wrist,  or  carpus,  of  man. 


Q.  How  are  these  bones  arranged  ?  —  A. 
They  are  ranged  in  tv^o  rows,  or  ders ;  one 
of  the  number,  trapezium,  is  located  in  the 
posterior  part  of  the  carpus. 

Q.  Name  the  bones  of  the  first  row  ?  — 
A.  Scaphoid,  lunar,  cuneiforme,  trapezium. 

Q.  Name  the  bones  crossing  the  second 
row  ?  —  A.  Pisiform,  trapezoid,  magnum, 
unciform. 

Q.  What  is  the  general  form  and  situa- 
tion of  each  of  the  bones  of  the  first  row? 
—  A.  The  OS  scaphoides  is  semi-ovoid  in 
form,  its  superior  surface  is  sigmoid  and 
smooth,  the  inferior  surface  is  somewhat 
oval,  and  rests  upon  the  trapezoides  and 
magnum  of  the  second  row.  Its  internal 
surface  comes  in  contact  with  the  os  lunare. 
The  OS  lunare  is  the  second  bone  of  the  first 
row ;  it  articulates  superiorly  with  the 
brachii ;  inferiorly,  with  the  ossa  magnum 
and  unciforme ;  its  superior  surface  is  trian- 
gular ;  inferior,  oblong ;  on  one  side,  inter- 
nally, it  articulates  with  the  scaphoid,  on 
the  other  with  the  cuneiforme.  The  cunei- 
forme is  known  as  the  external,  yet  smallest 
bone  of  the  knee.  Its  superior  surface  is 
concave  ;  inferior,  smooth ;  its  internal  sur- 
face articulates  with  the  os  lunare,  and  pos- 
teriorly it  unites  with  the  trapezium. 

Q.  What  is  the  general  form  and  situa- 
tion of  each  of  the  bones  of  the  second 
row  ?  —  A.  The  os  trapezoides  is  situated 
on  the  inner  side  of  the  knee,  resting  on  the 
inner  splent  bone,  and  articulating  with  the 
OS  magnum ;  its  form  is  that  of  an  irregular, 
curvated,  flattened  cone ;  its  superior  surface 
is  convex,  and  its  inferior  flat.  The  os 
magnum  is  the  middle  bone  of  the  second 
row,  and  is  known  as  the  largest  bone  of 
the  knee.  Its  superior  surface  presents  two 
articulatory  surfaces,  one  sigmoid  and  ob- 
long for  the  OS  lunare,  and  the  other  ovoid 
and  flat,  to  correspond  with  the  surface  of 
OS  scaphoides;  its  interior  surface  is  flat, 
and  articulates  with  large  metacarpal  bone. 
The  OS  unciform  is  situated  on  the  outer 
side  of  the  second  row,  and  in  form  resem- 
bles a  blunt  hook;  its  superior  surface  is 
convex;  its  inferior  irregular,  articulating 
with  the  outer  splent  and  cannon.     The  os 


46 


ANATOMY   AND   PHYSIOLOGY   OF 


trapezium  is  situated  in  the  posterior  part 
of  the  carpus,  and  presents  two  smooth  sur- 
faces for  articulation  with  tlie  ossa  cunei- 
forme  and  brachii.  Its  external,  lateral  sur- 
face is  convex ;  its  internal  concave ;  its 
superior  border  gives  attachment  to  the 
flexores  metacarpi ;  and  into  the  inferior  is 
inserted  a  ligament.  The  ossa  pisaformoe 
— for  sometimes  there  are  two  present  —  is 
situated  posterior  to  the  trapezoides ;  its 
form  is  orbicular  or  pea-shape. 

METACARPAL     BONES. 

The  metacarpal  bones  are  three  in  num- 
ber, viz :  metacarpus  magnum,  1 ;  metacar- 
pus parvum,  2.  There  seems,  however,  so 
great  a  disproportion  between  the  os  mag- 
num and  ossa  parva,  that  the  former  may 
be  considered  as  the  principal  support  of 
the  fore  extremities. 

Q.  What  is  the  situation  of  the  metacar- 
pus ?  —  A.  Immediately  beneath  the  carpus. 

Q.  Describe  the  form  of  the  metacarpi 
magnum.  —  A.  It  is  a  long  cylindrical 
bone,  presenting  on  its  anterior  surface  a 
circular,  smooth  appearance ;  its  posterior 
surface  is  somewhat  flattened  and  depressed. 

Q.  How  is  the  bone  divided  ?  —  A.  Into 
a  body,  and  two  extremities. 

Q.  Describe  the  extremities.  —  A.  The 
superior  presents  a  smooth  articulatory  sur- 
face, tapering  towards  its  outer  edges,  yet 
more  depressed  on  its  inner  and  posterior 
part ;  in  the  anterior  region  is  a  roughened 
prominence,  for  the  insertion  of  the  extensor 
metacarpi,  and  on  the  lateral  side  of  the 
bone  are  eminences  which  afford  insertion 
for  the  lateral  ligaments.  The  inferior  ex- 
tremity presents  a  pulley-like  surface,  with 
two  unequal  condyloid  surfaces,  separated 
by  a  semi-circular  eminence,  which  corre- 
sponds to  a  counterpart  found  on  the  supe- 
rior end  of  the  suffraginis. 

Q.  What  are  the  articulations  of  the 
metacarpi  magnum  ?  —  A.  It  articulates  su- 
periorly with  the  carpus  ;  inferiorly,  with  the 
OS  suffraginis ;  posteriorly  and  laterally,  with 
the  ossa  sqoamoidea,  and  metacarpi  parva. 

OSSA   METACARPI    PARVA  (sPLENT    BONES). 

Q.  How  many  bones  compose  the  ossa 


metacarpi  parva  ?  —  A.  Two  :  external  and 
internal. 

Q.  Describe  their  situation.  —  A.  They 
are  attached  to  the  lateral  and  posterior 
parts  of  the  metacarpi  magnum. 

Q.  How  do  you  divide  them  ?  —  A.  Into 
bases,  middles,  and  apices. 

Q.  Describe  the  base.  —  A.  It  is  sur- 
mounted by  a  smooth  articulatory  surface, 
corresponding  to  the  inferior  portion  of  a 
part  of  the  knee  joint. 

Q.  Describe  the  middle.  —  A.  It  is  tri- 
facial :  the  anterior  surface  is  roughened 
for  the  insertion  of  inter-articular  tissue, 
which  connects  it  with  the  cannon ;  the  inner 
surface  is  excavated;  the  outer  surface  is 
rounding,  and  terminates,  posteriorly,  acu- 
minately. 

Q.  Describe  the  apex.  —  A.  It  tapers,  and 
ends  in  a  tubercle,  which  curvates  in  an 
inferior  and  superior  direction. 

Q.  How  do  the  ossa  metacarpi  parva 
differ  ?  —  A.  The  external  is  generally  larger 
than  the  internal,  and  has  a  broader  articu- 
latory surface. 

Q.  What^one  does  the  external  splent 
articulate  with  ?  —  A.  The  unciform. 

Q.  What  bone  does  the  internal  splent 
articulate  with  ?  —  A.  The  trapezoid. 

Q.  How  are  the  splents  connected  to  the 
cannon  ?  —  A.  By  cartilago-ligamentous  tis- 
sue. 

Q.  What  changes  does  this  cartilaginous 
tissue  undergo,  subsequent  to  adult  life  ?  — 
A.  In  a  majority  of  cases  it  becomes  ossified. 

PASTERN    BONE    (oS    SUFFRAGINIs). 

Q.  Describe  the  location  of  this  bone.  — 
A.  It  is  located  beneath  the  cannon,  and 
takes  an  oblique  direction  from  the  same ; 
it  articulates  superiorly  with  the  cannon; 
posteriorly  with  the  ossa  sesamoidea. 

Q.  Describe  the  form  of  the  os  suffra- 
ginis. —  A.  It  is  a  flattened  cylinder,  yet  its 
superior  portion  is  more  bullcy  than  the  in- 
ferior ;  it  is  generally  considered  as  being 
about  one-third  the  length  of  the  cannon, 
and  is  divided  into  a  body,  superior  and 
inferior  extremities. 

Q.  Describe  the  body  of  the  os  suffra- 


THE  HOESE. 


4t 


ginis.  —  A.  The  body  presents  two  surfaces, 
anterior  and  posterior ;  the  anterior  is  con- 
vex, the  posterior  flattened  and  uneven ;  it 
lessens  in  bulk  in  an  inferior  direction. 

Q.  HoviT  is  the  superior  extremity  of  the 
pastern  bone  recognized  from  the  inferior  ? 

—  A.  The  superior  is  the  largest,  and  pre- 
sents two  shallow  articular  cavities;  between 
them  is  a  groove,  which  receives  the  central 
eminence  of  the  inferior  extremity  of  the 
cannon  bone.  The  inferior  extremity  is 
much  smaller  than  the  superior;  it  is  bi- 
convex, and  consists  of  two  articular  con- 
vexities, separated  by  a  transverse  shallow 
depression. 

SESSAMOID     BONES     (oSSA    SESSAMOID^). 

Q.  Where  are  the  two  sessamoids  situ- 
ated ?  —  A.  At  the  posterior  part  of  the 
articulation  formed  by  the  cannon  and 
pastern  bones. 

Q.  What  is  the  form  of  these  bones  ?  — 
A.  Trapezoid:  three  sides  present  triangular 
faces,  whose  apices  unite  in  one  point,  which 
is  directed  upwards  ;  the  bases  of  the  same 
form  a  fourth  side,  which  is  turned  down- 
wards ;  and  are  therefore  divided  into  three 
sides,  base,  and  apex. 

Q.  Give  a  general  description  of  the 
faces  or  surfaces  of  these  bones.  —  A.  They 
are  known  as  anterior,  posterior,  and  lateral 
faces ;  the  anterior  are  excavated,  smooth, 
and  articulatory,  and  along  their  inward 
borders — which  are  opposed  to  each  other 

—  are  levelled  off,  so  that  the  two  form  a 
groove  for  the  reception  of  the  central 
eminence  of  the  inferior  portion  of  the  can- 
non. The  posterior  surfaces  are  convex  and 
rough ;  the  lateral  surfaces  are  grooved  and 
roughened;  the  bases  are  narrow  and  uneven. 

Q.  What  appears  to  be  the  qbject  in  ex- 
cavating the  anterior  surfaces  of  these 
bones  ?  —  A.  To  extend  the  articulatory 
surface  of  the  pastern  joint,  and  admit  of 
extensive  anterior  and  posterior  motion. 

Q.  For  what  purposes  are  the  posterior 
surfaces  roughened  ?  —  A.  For  the  insertion 
of  the  suspensory  ligaments. 

Q.  What  occupies  the  cavity  which 
occurs  in  consequence  of  miiting  the  inter- 


nal surfaces  of  these  bones  ? — A.  The  flexor 
tendons. 

Q.  What  ligaments  are  inserted  into  the 
bases  of  these  bones  ?  —  A.  The  long, 
short,  and  crucial  ligaments. 

CORONET  BONE  (oS  CORON^). 

The  OS  cor  once  is  situated  beneath,  or 
rather  inferiorly,  to  the  pastern,  and  may 
therefore  be  termed  the  inferior  pastern; 
it  occupies  a  location  between  the  superior 
pastern  and  coffin  bone. 

Q.  Describe  the  os  coronae,  or  inferior 
pastern.  —  A.  It  presents  a  square  body ;  its 
breadth,  however,  somewhat  exceeds  its 
longitudinal  measurement.  It  has  four  sur- 
faces, viz.,  superior,  inferior,  anterior,  and 
posterior ;  the  superior  surface  is  bi-concave, 
corresponding  to  the  projections  of  the 
superior  pastern ;  the  inferior  surface  is  bi- 
convex, consisting  of  two  condyloid  prom- 
inences, separated  by  a  slight  transverse 
depression,  corresponding  to  the  articulatory 
surface  of  the  coffin-bone ;  the  anterior  sur- 
face is  convex,  yet  rough  and  irregular ;  the 
posterior  surface  is  quite  smooth,  yet  exca- 
vated. 

Q.  What  are  the  connections  of  the  oa 
coronEB  ?  —  A.  It  connects  with  the  pastern, 
coffin,  and  navicular  bones. 

BONES  OF  THE  FOOT. 

THE    COFFIN  BONE  (oS    PEDIs). 

The  coffin  bone  is  considered  as  the  base 
of  the  osseous  structure  of  the  fore  extremity. 

Q.  What  is  the  form  of  the  coffin  bone  ? 
—  A.  It  presents  a  semilunar  outline;  an- 
teriorly and  superiorly  it  is  convex ;  pos- 
teriorly and  inferiorly  it  is  concave ;  it  is 
divided  into  wall,  sole,  tendinous  surface, 
articulatory  surface,  and  wings. 

Q.  Describe  the  wall.  —  A.  It  is  a 
miniature  of  the  form  of  the  hoof;  it  exMbits 
a  porous  and  furrowed  surface,  and  has  in- 
numel-able  perforations,  varying  in  size  and 
form ;  its  superior  part  is  surmounted  by 
the  coronal  process;  the  inferior  edge  of  the 
wall  is  somewhat  oval,  and  is  notched  and 
serrated. 


48 


ANATOMY  AND  PHTSIOLOGY  OP 


Q.  What  are  the  uses  of  the  porosities 
and  furrows  ?  —  A.  They  serve  as  so  many 
attachments  for  the  fibrous  tunic  of  the 
sensible  laminae. 

Q.  Wliat  name  is  generally  applied  to 
the  largest  of  the  perforations  found  in  the 
coffin  bone  ?  —  A.  They  are  termed  for- 
amina?. 

Q.  What  occupies  these  foramina^  ?  — 
A.   Blood-vessels  and  nerves. 

Q.  Describe  the  sole  of  the  cofRn  bone  ? 
—  A.  The  sole  exhibits  a  broad,  uniform, 
concave  surface,  resembling  in  most  cases 
the  figure  of  the  inferior  part  of  the  hoof;  it 
has  porosities  similar  to  those  formed  on 
the  wall ;  it  is  bounded  anteriorly  and  later- 
ally by  the  circumferent  edge  of  the  w^all ; 
posteriorly,  by  a  sharp,  uneven,  semi-circular 
edge,  which  divides  it  from  the  tendinous 
surface. 

Q.  What  do  we  find  on  the  tendinous 
surface? — A.  1st,  a  rough  depression  in 
its  fore  and  middle  part,  marking  the  inser- 
tion of  the  tendo  perforans.  2ndly,  two 
lateral  grooves,  passing  obliquely  inwards, 
and  terminating  each  in  a  large  foramen. 
3rdly,  a  porous  space  intermediate  between 
the  two  former  divisions,  into  which  is  fijced 
the  inferior  navicular  ligament. 

Q.  What  occupies  the  lateral  grooves?  — 
A.  The  trunks  of  the  arteries  and  nerves 
which  occupy  the  interior  of  the  coffin  bone. 

Q.  What  are  the  peculiarities  of  the  ar- 
ticulatory  surface  of  the  coffin  bone  ?  —  A. 
It  has  two  lateral  depressions,  which  extend 
posteriorly  to  the  alae ;  a  broad  eminence 
runs  transversely  between  them  ;  this  emi- 
nence is  terminated  in  front  by  the  coronal 
processes,  having  an  incurvation  backwards ; 
behind  it,  the  surface  is  bevelled  off,  to 
which  part  is  opposed  the  navicular  bone ; 
the  depressions  alluded  to  are  deepened  by 
the  prominent  edge  running  around  the  an- 
terior and  lateral  parts. 

Q.  What  portion  of  the  coffin  bone  does 
the  articulatory  surface  .occupy? — *A.  The 
superior  part. 

Q.  What  is  the  form  of  this  surface  ?  — 
A.    It  is  half-moon  shaped. 

Q.   Describe  the  alae,  or  wings  ?  —  They 


consist  of  a  protuberance  on  the  posterior 
part  of  each  side  of  the  coffin  bone ;  the 
protuberance,  however,  is  generally  bifid; 
the  lower  portion  which  is  the  largest,  is 
irregular  and  asperous,  and  projects  in  a 
posterior  direction  ;  the  upper  portion  is  tu- 
bercular, yet  smooth ;  between  the  divisions 
of  the  alae  is  a  notch,  which,  at  a  certain 
period  in  the  life  of-  the  animal  becomes  a 
perfect  foramen. 

Q.  What  is  attached  to  the  irregular  sur- 
face of  the  larger  division  of  the  alae  ?  —  A. 
The  cartilage  of  the  foot. 

Q.  What  is  affixed  to  the  tuberculated 
portion  of  the  alae  ?  —  A.  The  coffin  liga- 
ments. 

Q.  What  vessel  passes  through  the 
notch  ?  —  A.  The  lateral  artery. 

Q.  What  is  there  remarkable  about  the 
structure  of  the  coffin  bone  ?  —  A.  It  has  a 
spongy,  fragile  texture,  pervaded  in  every 
direction  by  minute  canals  for  the  trans- 
mission of  blood-vessels  and  nerves ;  it  dif- 
fers very  essentially  from  many  bones  of 
the  body,  which,  in  heakhy  subjects,  are 
remarkable  for  compactness  and  solidity. 

NAVICULAR  BONE  (oS  NAVICULARe). 

Q.  What  is  the  general  form  and  division 
of  the  navicular  bone  ?  —  A.  It  is  semi-lu- 
nar :  its  lunated  border,  however,  only  forms 
about  one  third  the  circle  of  its  dimensions ; 
it  is  divided  into  two  surfaces,  two  borders, 
and  two  extremities. 

Q.  Where  is  this  bone  situated?  —  A. 
At  the  posterior  part  of  the  coffin  joint. 

Q.  Describe  the  superior  and  inferior  sur- 
faces of  the  navicular  bone.  —  A.  The 
superior  surface  bears  a  corresponding 
aspect  to  the  articulating  surface  of  the 
coffin  bone,  having  two  superficial  lateral 
depressions,  with  an  eminence  between 
them.  The  inferior  surface  is  also  articu- 
latory ;  and  exhibits  lateral  depressions  yet 
more  superficial  than  the  superior;  it  has 
also  an  eminence  across  the  middle,  nar- 
rower yet  more  prominent  than  the  former. 

Q.  Name  the  tendon  which  articulates 
over  the  inferior  surface.  —  A.  Tendo  per- 
forans. 


THE  HORSE. 


Q.  Describe  the  borders.  —  A.  The  bor- 
ders are  lunated  and  straight :  the  lunated 
is  broadest  in  the  centre,  and  narrows  to- 
wards the  extremities ;  superiorly  it  has  a 
smooth  narrow  strip  of  surface  along  the 
middle,  which  is  adapted  to  the  bevelled 
portion  of  the  articulatory  surface  of  the 
coffin  bone ;  the  part  beneath  is  fluted  and 
porous,  into  which  is  inserted  a  ligament 
which  connects  it  with  the  coffin  bone. 
The  straight  border  is  thinner  than  the 
opposite  one ;  superiorly  it  is  rough  and 
porous ;  inferiorly  it  is  smooth  -and  lipped. 

Q.  What  is  the  form  and  direction  of 
the  extremities  of  the  navicular  bone  ?  —  A. 
They  are  obtusely  pointed,  one  directed 
outward  and  the  other  inward. 

Q.  What  ligaments  are  inserted  into  the 
extremities  ?  —  A.  The  lateral  ligaments. 

HIND    EXTREMITIES. 

Q.  What  is  the  situation  of  the  hind 
extremities? — A.  They  occupy  the  inferior 
and  posterior  parts  of  the  pelvis,  and  sup- 
port the  posterior  parts  of  the  trunk. 

Q.  How  are  the  bones  of  the  hind  ex- 
tremities divided?  —  A.  They  are  thus 
divided :  Femur,  stifle,  thigh,  hock,  leg,  pas- 
tern, coronet,  and  foot. 

Q.  Name  the  bones  comprising  these 
parts.  —  A. 

FEMUR. 
STIFLE   BONE. 

Patella. 

THIGH  BONES. 

Tibia  and  Fibula. 

HOCK  BONES. 

Astragalus,  Os  calcis. 

Cuboid  bone, 
Three  Cuneiform  bones. 

BONES  OF  THE  LEG. 

Metatarsi  Magnum. 
Metatarsi  Paryieum,  t-^-o  bones  (splents). 

PASTEP>N  JOINT. 

Ossa  Sessamoidse  (two  bones), 
Os  Suffiraginis  (pastern). 

CORONET. 

Os  Corona. 

BONES   OF   THE  FOOT. 

Os  Pedis  find  Os  Naviciilare. 

7 


Q.  Where  is  the  femur  situated  ?  —  A. 
Between  the  pelvis  and  thigh  bones. 

Q.  How  is  it  divided?  —  A.  Into  a  body 
and  two  extremities. 

Q.  What  are  the  peculiarities  of  the 
superior  extremity  ?  —  A.  It  consists  of  two 
parts :  a  hemispherical,  smooth,  articulatory 
head,  directed  upwards  and  inwards,  and 
joined  to  the  body  by  a  flattened  neck, 
and  exhibiting  on  its  inner  side  a  fissure, 
into  which  is  fixed  the  teres  or  round  liga- 
ment. The  other  part  is  a  large  irregular 
projection  at  the  base,  and  posterior  to  the 
same  is  a  deep  oval  cavity ;  at  the  superior 
part  is  a  roughened  crest ;  inwardly  it  pre- 
sents a  concave,  smooth  surface. 

Q.  What  is  the  proper  name  of  the  pro- 
jection?—  A.  The  great  external  tro- 
chanter. 

Q.  What  muscles  are  inserted  into  the 
the  same  ?  —  A.  The  gluteii. 

Q.  What  is  inserted  into  the  concave 
smooth  surface?  —  A.  The  capsular  liga- 
ment. 

Q.  What  is  the  form  of  the  body  of  the 
OS  femoris  ?  —  A.  It  is  cylindrical. 

Q.  How  does  it  correspond  in  size  and 
weight  with  other  bones  of  the  body  ?  —  A. 
It  is  the  longest  and  weightiest. 

Q.  What  is  the  form  of  inferior  extrem- 
ity ?  —  A.  It  is  broad  and  thick,  and  has  a 
trochleal  prominence  and  two  condyles. 

Q.  Give  a  description  of  the  same.  —  A. 
The  articular  or  pully-like  surface  anteriorly 
consists  of  a  broad,  semi-circular  groove 
bounded  on  either  side  by  a  prominence ; 
the  condyles  much  resemble  each  other, 
excepting  that  the  external  is  the  thickest, 
and  the  internal  most  projecting;  they 
exhibit  prominent,  convex,  articulatory  sur- 
faces ;  on  their  sides  are  rough  eminences ; 
between  them  is  a  deep  fossa ;  at  the  base 
of  the  external  condyle  is  a  pit. 

Q.  What  articulates  over  the  pulley-like 
surface  ?  —  A.  The  patella  or  stifle  bone. 

Q.  What  is  inserted  into  the  rough  emi- 
nences ?  —  A.  The  lateral  ligaments. 

Q.  What  occupies  the  fossa  ?  —  A.  The 
inter-articular  ligament. 


50 


ANATOMY  AND   PHYSIOLOGY   OP 


Q.  What  is  inserted  into  the  pit  ?  —  A. 
The  tendon  of  the  extensor  pedis. 

Q.  What  is  the  state  of  this  bone  during 
colthood  ?  —  A.  Extremities  are  attached  to 
the  body  of  the  bone  by  means  of  cartilage. 

Q.  What  changes  do  the  extremities 
undergo  just  prior  to  adult  life  ?  —  A.  They 
become  consolidated  with  the  body  of  the 
bone. 

STIFLE    BONE    (pATELLa). 

Q.  What  is  the  situation  of  the  patella  ? 

—  A.  It  is  situated  on  the  anterior  and  infe- 
rior extremity  of  the  femur. 

Q.  What  is  its  general  form  ?  —  A. 
Quadrangular,  convex  externally,  irregularly 
concave  internally. 

Q.  How  is  it  divided  ?  —  A.  Into  three 
surfaces  and  four  angles. 

Q.  Describe  the  surfaces.  —  A.  The  an- 
terior surface  is  convex,  yet  quite  prominent 
in  the  centre ;  it  has  a  roughened  surface, 
and  is  porous.  The  superior  surface  is 
angular,  uneven,  and  roughened.  The  pos- 
terior surface  is  articulatory,  and  unequally 
divided  by  an  eminence  running  across  it 
into  two  shallow  concavities,  which  are 
adapted  to  the  condyles  of  the  inferior  ex- 
tremity of  the  femur. 

Q.  Describe  the  form  of  the  angles  of  the 
patella.  —  A.  They  are  obtuse. 

Q.  Why  is  the  anterior  surface  of  the 
bone  roughened  ?  —  A.  For  the  insertion  of 
tendinous  and  ligamentary  attachments. 

Q.  What  is  implanted  into  the  uneven 
and  roughened  part  of  the  superior  border  ? 

—  A.  The  tendons  of  the  rectus  and  vasti 
muscles. 

Q.  What  is  inserted  into  the  inferior  and 
lateral  angle?  —  A.  The  ligamentum  pa- 
tella. 

Q.  What  are  the  connections  of  this 
bone  ?  —  A.  It  is  connected  to  the  inferior 
portion  of  the  femur  by  tendinous  and 
capsular  ligaments ;  to  the  tibia  it  is  con- 
nected by  similar  ligaments. 

THIGH    BONES    (tIBIA    AND    FIBULa). 

In  consequence  of  a  horse  having  a  very 
large  femur,   and  that  bone  appearing  to 


enter  into  the  composition  of  the  haunch, 
the  tibia  and  fibula  are  termed  thigh  bones, 
although  in  man  they  are  termed  bones  of 
the  leg ;  the  fibula  of  the  horse,  however,  is 
a  very  small,  slender  bone,  affixed  to  the 
superior  part  of  the  external  side  of  the 
tibia. 

Q.  What  is  the  situation  of  the  thigh 
bone  ?  —  A.  It  is  situated  between  the  stifle 
and  hock. 

Q.  What  is  the  form  of  this  bone  ?  —  A. 
It  is  long,  straight,  prismatic ;  its  superior 
extremity  is  larger  than  the  inferior. 

Q.  What  is  its  direction  ?  —  A.  Oblique 
in  a  contrary  direction  to  the  femur. 

Q.  How  is  the  tibia  divided  ? — A.  Into 
a  body,  superior  and  inferior  extremities. 

Q.  What  is  the  general  form  of  the 
body  ?  —  A.  It  is  irregularly  triangular,  the 
posterior  face  is  broadest,  the  anterior  angle 
is  rounded,  and  the  sides  are  roughened. 

Q.  What  is  peculiar  to  the  superior  ex- 
tremity of  the  bone  ?  —  A.  We  find  two 
iri'egular  ovoid  articulatory  surfaces,  corre- 
sponding to  the  eminences  on  the  inferior 
extremity  of  the  femur  ;  these  are  separated 
by  an  acute  elevation,  and  two  fossa,  into 
which  is  inserted  the  lateral  ligament. 

Q.  Describe  the  inferior  extremity.  —  A. 
It  is  flattened,  and  has  two  deep  articular 
grooves  running  in  an  anterior  and  posterior 
direction  ;  its  exterior  margin  is  roughened. 

Q.  What  are  its  connections  ?  —  A.  It 
connects  with  the  femur  and  patella  supe- 
riorly ;  inferiorly,  with  the  bones  of  the  hock. 

FIBULA. 

Q.  What  is  the  situation  of  the  fibula? 
—  A.  At  the  posterior  part  of  the  tibia. 

Q.  How  is  it  connected  to  the  tibia  ?  — 
A.  By  cartilago-ligamentous  substance. 

Q.  What  is  the  form  of  the  two  ends  of 
the  bone  ?  —  A.  The  superior  is  bulky,  flat- 
tened from  side  to  side,  and  roughened. 
The  inferior  is  slender  and  tapering,  and 
extends  about  half  way  down  the  tibia. 

BONES    OF    THE    HOCK     (tARSUs). 

The  tarsus,  or  hock,  comprises  a  part  of 
the   osseous   structure  of    the   horse,  that 


s^ 


EXPLANATIONS   OF  FIGURE  VI. 


NO.    1.  —  FORE  EXTREMn'IES. 

/• 

The  ulnar. 

34. 

Humerus. 

35. 

Radius. 

36. 

Carjjus. 

37. 

Metacarpus. 

38. 

Scssamoids. 

S.  01 

•39.  Os  suffraginis. 

40. 

Os  corona. 

41. 

Os  pedis. 

The  above  description  also  answers  for  No.  3,  —  the  bony  structure 

NO.    2. —  MUSCULAR   STRUCTURE. 

LATEKAL  VIEW  OF  THE  KEAH-FOKE  EXTREMITY. 


s".  Extensor  metacarpi  magnus. 

/c".  Humero  cubital. 

n".  Levator  humero. 

p".  Flexor  metacarpi  estemus. 

x".  «".  Extensor  pedis. 

u".  ti".  V.  Flexor  tendons. 

v".  Flexor  tendons. 

z.    Suspensory  ligament. 

^.   The  hoof. 


NO.  4. 

ANTERIOR  VIEW  OF  THE  NEAR-FOEE  EXTEEMITT. 


s.  Extensor  metacarpi  magnus. 

t.  Extensor  metacarjoi  obliquus. 

x".  Extensor  pedis. 

?/".  Extensor  sufEi'aginis. 

fy.  The  hoof. 

8.  Bifurcation  of  the  suspensory  ligament. 


THE   HORSE. 


61 


every  veterinary  student  should  aim  to  be 
well  acquainted  vv^ith ;  it  is  a  part  that  seems 
to  be,  in  this  country,  more  liable  to  anchy- 
losis and  exostosis  than  any  other  region  ; 
here  is  the  seat  of  spavin,  and  no  one  can 
possibly  understand  the  nature  of  such  dis- 
ease unless  he  be  conversant  with  the  ana- 
tomical mechanism  of  the  hock.  The  hock 
corresponds  to  the  tarsus  or  instep  of  man, 
and  is  composed  of  six  bones,  viz.,  os  calcis, 
astragalus,  os  cuboides,  ossa  cuneiformis ; 
which  comprise  three  small  bones,  viz.,  ex- 
ternal, internal,  and  middle  cuneiforme.  We 
shall  first  consider  the  os  calcis. 

Q.  What  is  the  situation  of  the  os  cal- 
cis ?  —  A.  It  forms  the  posterior  projec- 
tion known  as  the  point  of  the  hock  —  the 
superior  and  posterior  bone  of  the  tarsus. 

Q.  Give  a  general  description  of  the 
bone.  —  A.  Its  figure  is  irregular ;  presents 
a  body,  tuberosity,  posterior  surface,  and 
base  ;  the  body  is  most  bulky  at  its  inferior 
part ;  as  a  whole,  it  is  irregularly  convex ; 
concave  and  expanded  at  its  base,  where 
it  presents  four  surfaces  for  articulation 
with  the  astragalus ;  the  tuberosity  is  ob- 
long, flattened  on  each  side,  and  terminates 
in  a  rough  tubercle,  into  which  is  inserted 
the  tendons  of  the  gastrocnemii.  It  is  sit- 
uated on  the  superior  part  of  the  hock. 

THE    KNUCKLE    BONE    (aSTRAGALUs). 

Q.  What  is  the  situation  of  the  astra- 
galus ?  —  A.  It  is  situated  in  the  superior 
part  of  the  hock,  and  is  the  principal  sup- 
port of  the  tibia. 

Q.  How  do  you  distinguish  it  from 
other  bones  ?  —  A.  It  is  readily  distin- 
guished by  its  double  pulley-like  articula- 
tory  surfaces,  which  consist  of  two  semi- 
circular prominences,  having  between  them 
a  deep  groove,  well  adapted  to  receive  the 
projection  found  on  the  inferior  extremity 
of  the  tibia. 

Q.  What  is  the  appearance  of  the  pos- 
terior surface  ?  —  A.  It  has  four  articulatory 
surfaces,  corresponding  to  those  of  the  os 
calcis. 

Q.  What  is  the  appearance  of  the  base 
or  inferior  extremity  ?  —  A.    It  has  an  irre- 


gularly flattened  articulatory  surface,  which 
comes  in  contact  with  the  large  cuneiform 
bone. 

CUBOID    BONE    (oS    CUBOIDEs). 

Q.  What  is  the  situation  of  the  cuboid 
bone  ?  —  A.  On  the  outer  part  of  the 
hock. 

Q.  How  is  the  bone  divided  ?  —  A.  Into 
four  surfaces,  viz.,  external,  internal,  supe- 
rior, and  inferior. 

Q.  How  do  you  distinguish  the  external 
from  the  internal  surface  ?  —  A.  The  exter- 
nal surface  is  broad,  irregular,  curved,  and 
roughened ;  on  the  other  hand,  the  internal 
is  excavated,  and  has  three  articulatory 
smfaces. 

Q.  How  does  the  superior  surface  differ 
from  the  inferior  ?  —  A.  The  superior  sur- 
face has  two  articulations,  with  a  fossa 
between  them ;  the  inferior  surfaces  are 
smaller,  and  correspond,  one  to  the  articula- 
tory head  of  the  splent  bone,  and  the  other 
to  the  cannon. 

large  cuneiform    bone  (os    cuneiforme 
magnum). 

Q.  What  is  the  situation  of  the  cunei- 
form bone  ?  —  A.  Directly  beneath  the 
astragalus. 

Q.  What  is  the  appearance  of  this  bone  ? 
—  A.  It  presents  a  triangular  form ;  its 
acute  termination  being  in  a  posterior  direc- 
tion, it  has  superior  and  inferior  surfaces, 
sides,  and  angles. 

Q.  How  is  the  superior  surface  distin- 
guished from  the  inferior  ?  —  A.  The  supe- 
rior surface  has  a  uniform  articulatory 
surface,  with  the  exception  of  a  small, 
rough  grove  running  to  its  centre,  from  the 
outer  side,  which  terminates  in  a  central 
pit.  The  inferior  sm-face  is  rather  convex, 
yet  presenting  a  flat  appearance  ;  its  poste- 
rior angle  has  an  articulatory  surface,  cor- 
responding to  that  of  the  cuboid  bone. 

Q.  What  are  the  articulations  of  this 
bone?  —  A.  It  articulates  with  the  astra- 
galus, cuboid,  middle  and  small  cunei- 
form bones. 


ANATOMY  AND   PHYSIOLOGY   OP 


middle  cuneiform  bone  (os  cuneiforme 
medium). 

Q.  What  is  the  situation  of  the  middle 
cuneiform  bone  ?  —  A.  It  is  situated  be- 
neath the  large  cuneiform. 

Q.  What  is  the  relative  size  of  the  ossa 
cuneiformis  ?  —  A.  The  one  beneath  the 
astragalus  is  the  largest ;  the  middle  is  the 
medium ;  and  that  at  the  posterior  part  of 
the  hock  is  the  smallest. 

small  cuneiform  bone  (o3  cuneiforme 
parvum). 

Q.  What  is  the  situation  of  the  small 
cuneiform  bone  ?  —  A.  It  is  situated  at  the 
posterior  part  of  the  hock. 

Q.  What  are  the  articulations  of  this 
bone  ?  —  A.  It  articulates  superiorly  with 
the  internal  angle  of  the  large  cuneiform ; 
anteriorly,  with  the  same  angle  of  the  mid- 
dle cuneiform ;  posteriorly,  with  the  inter- 
nal splent  bone  and  cannon. 

HIND    CANNON    (oS    METATARSI    MAGNUM). 

Q.  What  is  the  popular  name  of  the 
hind  cannon  ?  —  A.    Shank-bone. 

Q.  How  does  it  compare  in  length  with 
the  cannon  of  the  fore  extremities  ?  —  A.  It 
is  about  one-sixth  part  longer  than  the  fore 
cannon. 

Q.  Is  there  any  difference  in  the  supe- 
rior surfaces  of  the  fore  and  hind  cannons  ? 
— A.  Yes ;  the  superior  surface  of  the  fore 
cannon  corresponds  to  the  surfaces  of  the 
inferior  bones  of  the  carpus ;  the  superior 
extremity  of  the  hind  cannon  closely  resem- 
bles the  surfaces  of  the  middle  and  small 
cuneiform  bones,  and  also  that  of  the 
cuboid. 

Q.  How  do  the  hind  and  fore  cannons 
differ  in  conformation  ?  —  A.  The  bone  of 
the  hind  extremity  is  more  circular  and 
prominent,  anteriorly,  than  the  forward 
one. 

METATARSI    PARVIUM  (hIND  SPLENTS.) 

Q.  What  is  the  situation  of  the  metatarsi 
par\-ium?  —  A.  They  are  situated  at  the 
posterior  part  of  the  hind  cannon. 

Q.    How  are  the  hind  splents  recognized 


from  those  of  fore  limbs  ?  —  A.  The  hind 
splents  are  longer  than  the  fore  ;  their  bodies 
are  more  circular  and  prominent  forward, 
and  the  superior  extremities  correspond  to 
a  part  of  the  cuneiform  and  cuboid  bones ; 
while  the  superior  extremities  of  the  forward 
splents  correspond  to  a  portion  of  the  in- 
ferior row  of  the  bones  of  the  knee. 

We  now  come  to  the  bones  articulating 
beneath  the  inferior  extremity  of  the  hind 
cannon,  viz.,  pastern,  sessamoid,  coronet, 
coffin,  and  navicular  bones.  These,  according 
to  the  opinion  of  JNIr.  Percivall,  "  so  closely 
resemble  their  fellows  of  the  fore  extremity" 
that  we  shall  dispense  w4th  examinations 
regarding  them,  merely  remarking  that  the 
bones  of  the  hind  feet  are  generally  broader 
in  a  lateral  and  posterior  direction  than 
those  of  the  fore ;  the  pastern  and  coronet 
bones  are  somewhat  longer  than  their  fellows 
forward. 

BONES    OF    THE    EAR. 

Q.  Name  the  bones  of  the  ear. —  A. 
Malleus,  incus,  stapes,  and  orbiculare. 

Q.  What  is  the  form  of  the  malleus?  — 
A.    It  appears  to  resemble  a  mallet. 

Q.  Name  the  long  process  or  handle.  — 
A.    ]\Ianubrium. 

Q.    To  what  is  the  manubrium  attached? 

—  A.  To  the  membrana  tympani. 

Q.  Describe  the  form  of  the  incus.  —  A. 
It  is  said  to  resemble  a  blacksmith's  anvil, 
but,  probably,  approaches  nearer  to  the 
figure  of  a  molar  tooth  ;  it  has  a  depression 
on  its  surface,  which  receives  the  head  of 
the  malleus. 

Q.  Describe  the  stapes.  —  A.  It  resem- 
bles in  form  a  common  iron  stirrup,  yet  has 
a  more  triangular  appearance. 

Q.    With  what  bone  does  it  articulate? 

—  A.    The  OS  orbiculare. 

Q.  Describe  the  os  orbiculare. —  A.  It  is 
the  smallest  bone  of  the  body,  not  exceeding 
in  size  a  grain  of  mustard-seed. 

Q.  What  is  its  use  in  the  mechanism  of 
the  ear  ?  —  A.  It  forms  the  medium  of 
junction  and  communication  between  the 
incus  and  stapes,  and  facilitates  the  motions 
of  the  latter  bones. 


THE   HORSE. 


53 


OS    HYOIDES    (bone    OF    THE    TONGUe). 

Q.    What    is   the   situation   of    the   os 


hyoides 


A.    It  is  located  at  the  root  of 


the  tongue,  at  the  anterior  part  of  the  larynx. 

Q.  How  is  the  bone  divided  ?  —  A.  Into 
a  body  and  four  horns. 

Q.  What  is  the  form  of  the  body  ?  —  A. 
In  shape,  it  resembles  a  spur,  consisting  of 
neck  and  branches ;  the  neck  is  inserted 
into  the  root  of  the  tongue,  and  the  branches 
are  in  a  posterior  direction,  embracing  the 
superior  border  of  the  thyroid  cartilage. 

Q.  What  is  the  appearance  of  the  horns  ? 
—  A.  There  are  two  long  and  two  short 
horns ;  the  short,  or  inferior,  ascend  oblique- 
ly from  their  articulations  with  the  body  of 
the  bone,  and  terminate  in  oblong,  smooth 
extremities.  The  long  or  superior  horns 
constitute  two  long,  flattened,  thin  bones, 
extending  backward  in  a  horizontal  direc- 
tion from  the  summits  of  the  inferior  horns. 

Q.  What  are  the  connections  of  the  os 
hyoides  ?  —  A.  It  is  connected  with  the 
temporal  bone,  larynx,  pharynx,  tongue,  and 
some  of  the  muscles  of  the  neck. 

OF    THE    teeth. 

Q.  How  many  teeth  do  we  find  in  the 
jaws  of  the  adult  horse?  —  A.  Forty.  In 
the  mare,  however,  the  canine  teeth  are 
generally  imperfect  or  undeveloped. 

Q.  How  are  the  teeth  divided?  —  A. 
Into  tlu-ee  classes,  viz. :  incisors,  or  nippers ; 
molars,  or  grinders ;  canini,  or  tusks. 

A.  Enumerate  each  class.  —  A.  There 
are  twelve  incisors,  twenty-four  molars,  and 
four  canine. 

Q.  Is  there  anything  peculiar  about  the 
development  of  horses'  teeth  ?  —  A.  Yes  ; 
the  teeth  with  which  the  animal  is  furnished 
during  colthood  are  termed  temporary,  and 
are  generally  shed  ere  the  animal  arrives  at 
the  age  of  five ;  the  temporary  teeth  are 
twenty-four  in  number,  twelve  incisors  and 
twelve  molars  ;  they  differ  from  what  is 
termed  the  "  permanent  set,"  in  being  small- 
er and  whiter,  and  in  having  necks  or  con- 
tractions at  the  superior  part  of  the  fang, 
and  the  eminences  on  their  face  are  quite 


sharp.  The  converse  is  the  case  with  regard 
to  the  permanent  teeth. 

Q.  What  is  the  popular  theory  regarding 
the  periods  of  cutting  the  teeth? — A.  A 
foal  is  said,  at  birth,  to  be  in  the  act  of  cut- 
ting twelve  molars,  three  on  each  side  of 
the  jaw  bone;  at  this  time,  there  is  no  ap- 
pearance of  incisors ;  and  when  they  do 
appear,  which  period  vdU.  be  about  the 
second  or  third  week  from  birth,  sometimes 
sooner,  the  front  incisors  of  the  upper  jaw 
are  the  first  to  show  themselves,  and  be- 
tween the  fourth  and  fifth  week,  they  are 
succeeded  by  the  middle  incisors ;  the  side 
or  lateral  incisors  make  their  appearance 
between  the  sixth  and  tenth  month.  The 
animal  is  then  said  to  have  a  full  set  of 
temporary  teeth.  After  the  animal  has  at- 
tained his  first  year,  the  fourth  molars  make 
their  appearance.  Between  the  period  of 
the  first  and  second  years,  the  fifth  molars, 
in  each  side  of  the  jaw,  are  apparent.  Be- 
tween the  second  and  third  years,  the  front 
permanent  incisors  displace  the  temporary, 
and,  at  the  same  time,  the  first  temporary 
molars  are  shed,  and  replaced  by  the  perma- 
nent. Between  the  thfrd  and  fourth  j^ears, 
the  middle  temporary  incisors  are  succeeded 
by  the  permanent,  and  about  the  same  time 
the  second  temporary  molars  are  shed. 
During  the  inter\'al  of  the  fourth  and  fifth 
years,  the  lateral  permanent  incisors  appear ; 
the  sixth  and  last,  permanent  molars  are 
up,  and  then  the  tusks  also  appear.  At  this 
period  the  horse  is  said  to  have  a  full  mouth; 
a  complete  set  of  permanent  teeth.* 

We  have  now  arrived  at  an  era  (or  re- 

=*  On  this  side  the  Atlantic  we  are  not  in  possession  of 
any  reliable  information  as  regards  the  peiiods  of  cutting 
and  shedding  teeth ;  we  have  to  depend  entirely  on  English 
authoi-ity.  Their  theory  is,  that  the  age  of  a  race-horse  shall 
be  reckoned  from  the  month  of  May  in  the  year  of  his 
birth,  without  any  inquiiy  whatever  as  to  the  season, 
month,  or  day  of  foaling  ;  so  that  the  produce  of  January 
are  actually  four  months  older  than  by  reckoning,  or  as 
their  ages  appear  on  the  calendar,  and  these  arc  called 
early  foals ;  whereas  those  foaled  in  ilarch  are  denomi- 
nated late.  These  data  are  more  arbitraiy  than  truthful ; 
may  suit  the  convenience  of  English  turfmen,  but  will  not 
pass  current  among  om*  breeders,  —  who,  generally,  pay 
particular  attention  to  the  time  of  foaling,  and  date  the 
bu'th  of  the  colt  accordingly. 


54 


ANATOMY   AND   PHYSIOLOGY   OP 


markable  period)  in  the  age  of  the  horse ; 
have  briefly  considered  a  series  of  changes 
which  the  teeth  of  a  colt  undergo,  up  to 
the  period  of  maturity,  and  shall  now  turn 
our  attention  to  the  changes  observed  in 
the  process  of  wear  and  tear  of  the  perma- 
nent teeth. 


REMARKS  ON  THE  CHANGES 
WHICH  A  HORSE'S  TEETH 
UNDERGO. 

The  nippers  or  front  teeth  of  a  full- 
mouthed  horse,  just  having  shed  all  the 
temporary  ones,  present  a  beautiful  ap- 
pearance :  the  contrast  between  the  lily 
whiteness  of  the  teeth,  and  the  rose-tinted 
color  of  the  gums  and  their  membranes,  are 
never  so  much  the  subject  of  admiration  as 
at  this  period. 

Teeth,  when  first  cut,  present  a  sharp 
border  externally,  from  which  a  gi'adual 
depression  commences  until  the  internal 
border  is  reached ;  in  the  course  of  about 
a  year,  in  consequence  of  friction  on  the 
external,  and  growth  of  the  internal,  the 
surface  presents  two  elliptical  enamelled 
rims,  one  of  which  borders  the  face  of  the 
tooth,  the  other  encircles  the  depression  or 
pit. 

Within  this  pit  is  a  black  incrustation, 
which  is  denominated  "bean  "  or  "  mark ; " 
at  a  period  of  about  three  years  from  the 
time  of  cutting  the  permanent  teeth,  the  pit 
or  cavity  is  consolidated  or  filled  up,  and 
the  surface  of  the  tooth  is  worn  down  so  as 
to  present  a  comparatively  smooth  one. 
We  must  not  expect,  however,  to  find  the 
face  of  the  teeth  uniform ;  for  cribbers,  and 
voracious  feeders,  deface  the  surfaces  very 
much,  which  gives  to  the  teeth  the  appear- 
ance of  age.  Still,  a  good  judge,  who  takes 
into  consideration  not  only  the  appearances 
of  surfaces,  but  also  the  form  and  direction 
of  the  teeth  themselves,  is  not  apt  to  be 
deceived  regarding  the  age  of  a  full-mouthed 
horse. 

Pessina,  from  whose  work  Mr.  Percivall 
quotes,  concludes  that — 

"  At  the  age  of  eight  (in  most  horses). 


the  disappearance  of  the  marks  is  perfect: 
the  teeth  are  all  oval,  the  central  enamel 
upon  the  face  is  triangular,  and  nearer  to 
the  outward  than  the  inward  border,  and 
the  cavity  of  the  tooth  appears  within  tlie 
outward  border  like  a  yellowish  band  canied 
from  one  side  to  the  other. 

"  At  nine  years,  the  front  teeth  appear 
round,  the  middle  and  the  lateral  contract 
their  oval  faces,  and  the  central  enamel  di- 
minishes and  approaches  the  inward  border. 

"  At  ten,  the  middle  teeth  become  round, 
and  the  central  enamel  has  approximated 
the  inward  border  and  is  rounded. 

"  At  eleven,  the  middle  teeth  are  rounded, 
and  the  central  enamel  is  almost  worn  off 
the  posterior  incisors. 

"  At  twelve,  the  lateral  teeth  are  rounded, 
the  central  enamel  has  quite  disappeared : 
the  yellow  band  has  grown  wider,  occupies 
the  centre  of  the  face  of  the  tooth,  and 
the  central  enamel  continues  in  the  teeth 
of  the  upper  jaw. 

"  At  thirteen,  all  the  incisors  are  rounded, 
the  sides  of  the  front  teeth  spread  out,  and 
the  central  enamel  continues  in  the  upper 
jaw,  but  is  round  and  approaches  the  inward 
border. 

"  At  fourteen,  the  faces  of  the  front  inci- 
sors put  on  a  triangular  appearance,  the 
middle  grow  out  at  their  sides,  and  the  cen- 
tral enamel  of  the  upper  teeth  diminishes, 
but  still  exists. 

"  At  fifteen,  the  front  teeth  have  become 
triangular,  the  middle  enter  upon  that 
figure,  and  the  central  enamel  of  the  upper 
jaw  is  still  visible. 

"  At  sixteen,  the  middle  are  triangular, 
the  lateral  commence  that  shape,  and  the 
enamel  of  the  upper  teeth  has  disappeared. 

"  At  seventeen  the  triangular  figures  of 
the  posterior  jaw  are  completed ;  but  their 
triangles  are  equilateral  until  the  eighteenth 
year.  Then  their  sides  lengthen  in  succes- 
sion from  the  front  to  the  lateral  teeth,  in 
such  a  manner  that  — 

"  At  nineteen,  the  front  teeth  are  flat- 
tened from  side  to  side ; 

"  At  twenty,  the  middle  incisors  have 
taken  on  the  same  shape ;  lastly  — 


THE   HORSE. 


55 


"  At  twenty-one  the  lateral  teeth  are  also 
flattened." 

Professor  Passini  *  "  systematically  di- 
vides the  lifetime  of  the  horse,  which  he 
computes  at  thirty  years,  into  six  periods, 
that  take  their  rise  from  and  are  determined 
by  an  equal  number  of  changes  the  teeth 
naturally  undergo,  in  regular  succession. 

"  The  first  period  is  that  during  which 
the  animal  retains  aU  or  any  of  his  milk 
teeth ;  it  extends  irom  birth  to  the  fifth  year. 

"  The  second  period  includes  the  sixth 
year,  and  continues  so  long  as  the  marks 
remain  visible  upon  the  faces  of  the  pos- 
terior incisors;  which  is  generally  about 
three  years. 

"  In  many  instances,  however,  and  espe- 
cially among  horses  that  have  been  kept  at 
pasture,  the  faces  of  the  front  teeth,  and 
sometimes  those  of  the  middle,  are  worn  off" 
earlier. 

"  The  third  period  is  that  during  which 
the  teeth  retain  the  oval  form.  As  the  pits 
and  marks  degenerate,  the  face  of  the  tooth 
slowly  and  gradually  undergoes  a  deviation 
of  figure,  from  that  of  a  pretty  regular  ellip- 
sis, whose  long  to  its  short  axis  bears  the 
proportion  of  six  to  three,  to  an  irregular 
one,  in  which  these  proportions  are  as  five 
to  four.  This  period  requires,  on  an  aver- 
age, the  space  of  six  years  for  its  comple- 
tion ;  the  front  teeth  enter  it  in  the  seventh 
and  conclude  it  at  the  expnation  of  the 
twelfth ;  the  middle  pass  through  it  one 
year  later ;  and  the  lateral,  or  side  teeth,  one 
year  later  still. 

"  In  the  fourth  period  the  faces  of  the 
teeth  assume  a  circular  figure,  and  hence 
have  been  denominated  round.  At  the 
commencement  of  this  period,  the  breadth 
of  the  face  to  its  thickness  is  as  5  to 
4 ;  at  the  conclusion,  it  measures  in  an 
inverse  ratio,  as  4  to  5  ;  about  the  middle 
of  it,  the  diameters  are  equal.  This  period 
also  endures  six  years  ;  so  that  the  front 
teeth,  which  enter  it  in  the  thirteenth  year, 
complete  it  by  the  expu-ation  of  the 
eighteenth ;  the  middle  follow  one  year 
later  ;  the  lateral,  one  year  later  still. 

*  See  Percivall's  Lectures. 


.  "  During  the  fifth  period,  the  face  of  the 
teeth  deviates  by  slow  degrees  from  the 
round,  and  passes  into  the  triangular  state. 
In  the  beginning,  its  thickness  exceeds  its 
breadth  as  5  does  4 ;  in  the  end,  as  6  does 
3.  It  is  the  professor's  opinion,  yet  uncon- 
firmed by  experience,  that  this  period,  like- 
wise, on  an  average,  includes  a  space  of  six 
years;  the  front  teeth,  therefore,  complete 
it  with  the  twenty-fourth,  the  middle  with 
the  twenty-fifth,  and  the  lateral  with  the 
twenty-sixth  years. 

"  The  sixth  and  last  period  is  one,  in  the 
course  of  which  an  additional  angle  is 
projected  from  the  anterior  or  inferior  part 
of  the  tooth ;  Pessina  distinguishes  it  by 
the  epithet  biangular ;  he  has  never  met  with 
a  horse  that  had  lost  his  teeth  from  age ; 
but  he  has  seen  their  faces  eUiptrical  con- 
trariwise, looking  outwards  or  forwards. 
This  period  is  unlimited. 

"  In  the  anterior,  or  upper  jaw,  the  marks 
disappear  from  the  front  teeth  in  the  course 
of  the  ninth  year ;  from  the  middle  in  the 
tenth;  and  from  the  lateral  in  the  elev- 
enth. 

"  What  progress  these  upper  teeth  have 
not  made  in  transformation  during  the 
second  period,  equivalent  with  the  poste- 
rior, they  gain  it  in  the  third ;  notwith- 
standing the  depth  of  pit,  their  proportions 
are  then  the  same.  They  continue  three 
years  longer  in  the  second,  and  consequently 
are  only  three  in  the  third  period  ;  so  that, 
by  the  twelfth  year,  the  third  period  is 
completed  by  the  front  upper  teeth,  and 
so  on.  During  the  fourth,  fifth,  and  last 
periods,  the  changes  are  alike,  and  equally 
perceptible  in  either  jaw. 

"  So  far,  th^  upper  teeth  are  entitled  to 
an  equal  share  of  our  regard;  though,  in 
the  generality  of  cases,  they  need  not  be 
inspected.  In  such  a  remarkable  man- 
ner the  lateral  teeth  of  the  upper  jaw  wear 
away  so  that  they  often  appear  as  if 
notched  or  indented. 

"  In  regard  to  the  tusk  or  tush,  Pessina 
remarks  that  he  has  found  the  least  regu- 
larity in  its  changes  of  any  tooth.  The 
very  facts  that  the   tushes  are  not  in  all 


«« 


ANATOMY  AND  PHYSIOLOGY  OF  THE  HORSE. 


horses  cut  at  the  same  age,  thai  they  have 
little  or  no  attrition  against  each  other,  and 
that  they  are  worn  by  the  tongue  and  food, 
sometimes  more,  at  others  less,  should  lead 
us  to  draw  conclusions  from  them  with 
great  caution  ;  in  fact,  as  indications  of 
age,  they  can  only  be  trusted  to  when  they 
accord  with  the  incisors.  The  tush  or 
tusk  makes  its  appearance  by  the  fifth,  and 
is  completely  evolved  by  the  sixth  year. 
In  the  seventh,  the  apex  of  the  cone  is 
worn  off.  In  the  eighth,  its  furrows  grow 
shallow ;  in  the  ninth  they  arc  obliterated. 
Then  the  apex  gradually  wears  away ,  in 
the  twelfth  year  it  becomes  round ;  from 
which  time,  though  it  gradually  becomes 
shorter,  its  shape  varies  but  little.  But  it 
is  not  uncommon  to  see  the  tush  blunted 


like  an  acorn  in  the  ninth  year,  nor  to  find 
it  still  pointed  in  the  sixteenth  year. 

"  Pessina  concludes  his  account  of  the 
changes  to  which  the  teeth  are  subject, 
by  observing,  that,  as  they  are  dependent 
on  wear,  which  is  no  law  of  nature,  but 
an  effect  of  mechanical  and  accidental 
causes,  they  cannot,  but  under  certain  lim- 
itations, be  implicitly  relied  on." 

We  are  now  supposed  to  be  in  posses- 
sion of  some  of  the  most  important  facts 
tending  to  elucidate  the  changes  which  the 
teeth  undergo  ;  and,  in  view  of  making  our- 
selves more  conversant  with  this  subject, 
we  shall  re-commence  our  examinations, 
for  it  is  a  matter  of  the  highest  importance 
that  a  veterinary  surgeon  shall  understand 
the  method  of  ascertaining  a  horse's  age. 


EXAMINATIOXS   ON  THE  TEETH. 


Q.  Does  the  evolution  of  the  tush  always  indicate 
that  the  animal  is  five  years  of  age  ?  —  A.  No.  It  has 
been  seen  between  the  third  and  fourth  years. 

Q.  Which  teeth  do  you  place  the  most  reUance  on 
in  ascertaining  the  age  of  a  horse  ?  —  A.  The  side  or 
lateral  of  the  lower  jaw.  They  make  their  appearance 
last;  their  pits  are  the  last  to  disappear;  after  the 
age  of  eight  or  nine,  however,  the  pits  in  the  incisors 
of  the  upper  j  aw  are  also  indicative  of  age;  they,  being 
deeper,  of  course  remain  some  time  after  all  vestiges 
of  the  same  have  disappeared  in  the  lower  jaw. 

Q.  In  adult  life  is  there  any  continued  accretion  or 
after-growth  of  the  teeth?  —  A.  Yes.  If  it  were  not 
so,  the  animal  would,  in  course  of  time,  have  to  gather 
food,  and  grind  the  same  with  liis  gums  ;  for,  acccord- 
ing  to  the  law  of  iccar  and  tear,  destruction  of  the  in- 
struments —  grinders  of  food  —  must  more  or  less  reg- 
ularly take  place. 

Q.  What  changes  take  place  as  the  horse  advances 
in  age,  in  the  inchnation  of  the  incisors  ?  —  A.  They 
acquu-e  a  horizontal  direction. 

Q.  How  is  this  change  of  dhection  compensated  for 
in  the  grinders  ?  —  A.  The  faces  of  the  latter  are  worn 
down  by  friction,  and  thus  the  nippers  come  in  contact. 


Q.  Are  there  not  times  when  the  consumption  of  the 
faces  of  the  teeth,  by  friction,  is  not  in  proportion  to 
growth,  in  issue  from  the  socket  ?  —  A.  Yes. 

Q.  What  is  the  result?  —  A.  The  faces  of  the  grind- 
ers do  not  come  in  contact,  and  the  food  is,  conse- 
quently, imj^erfectly  masticated. 

Q.  How  is  tills  rectified  ?  —  A.  By  sawing  off  the 
nippers  to  their  natural  length. 

Q.  Taking  it  for  granted  that  there  is  a  time  when 
the  teeth  cease  to  grow,  how  do  you  account  for  the 
lengthy  teeth  observed  in  aged  horses  ?  —  A.  The  fang 
shrinks,  and  is  carried  upward  in  the  lower  and  down- 
ward in  the  upper  jaw,  and  the  gums  also  shrinli;  thus 
we  get  length  of  teeth. 

Q.  What  are  the  general  appearances  of  age,  micon- 
nected  with  the  teeth  ?  —  A.  The  muscles  of  the  head 
and  face  condense,  and  give  to  the  same  a  lean  appear- 
ance ;  the  cavities  above  the  eyes  are  deep ;  the  gums 
and  palate  become  pale  and  callous ;  the  submaxillary 
space  is  capacious,  and  gray  hairs  make  their  a])pcar- 
ance  in  various  places ;  the  neck  appears  small  and 
Anry,  the  withers  sharp,  the  back  cm'ves,  and  the 
limbs  appear  sinewy. 


MYOLOGY. 


PRELIMINARY    REMARKS    ON    THE    MUSCLES. 

To  the  naked  eye,  the  muscles  appear  to 
be  composed  of  fasciculi,  or  bundles  of 
fibres,  which  are  arranged  side  by  side  in 
the  direction  in  wliich  the  muscle  is  to  act, 
and  which  are  united  by  areolar  tissue. 
These  fasciculi  when  separated  appear  like 
simple  fibres,  but  when  examined  under  a 
microscope  are  found  to  be  themselves  fas- 
ciculi, composed  of  minuter  fibres,  bound 
together  by  delicate  filaments  of  areolar  tis- 
sue. By  carefully  separating  these,  we  may 
obtain  the  ultimate  muscular  fibre.  This 
fibre  exists  under  two  forms,  the  striated 
and  non-striated.  The  former  is  chiefly 
distinguished  by  the  transversely-striated 
appearance  which  it  presents.  The  non- 
striated  consist  of  a  series  of  filaments 
which  do  not  present  transverse  markings. 
At  an  early  stage  of  the  development  of 
muscular  fibre,  however,  there  is  no  differ- 
ence in  the  forms  of  either  striated  or  non- 
striated.  Both  are  simple  tubes,  containing 
a  granular  matter  in  which  no  definite 
arrangement  can  be  traced,  yet  presenting 
enlargements  occasioned  by  the  presence  of 
nuclei.  But,  whilst  the  striated  fibre  goes 
on  in  its  development,  until  the  cells  of  the 
fibrillsB  are  fully  produced,  the  non-striated 


j  fibre  retains  throughout  life  its  original 
embryonic  condition ;  the  contents  of  the 
tube  remaining  granular.  The  non-striated 
muscular  fibre  is  the  kind  of  structure  proper 
to  the  muscular  coat  of  the  alimentary 
canal,  bladder,  uterus,  trachea,  bronchial 
tubes,  etc.  They  seem  to  be  arranged  in  a 
parallel  manner  into  bands  or  fasciculi, 
without  any  very  definite  points  of  attach- 
ment. On  the  other  hand,  striated  muscular 
fibre  has  attachments  to  its  extremities  of 
fibrous  tissue,  through  the  medium  of  which 
it  exerts  its  contractile  power  on  the  part 
it  is  destined  to  move. 

At  the  truncated  extremity  of  the  striated 
muscles  we  find  tendons.  To  the  ordinary 
observer,  tendons  appear  to  unite  abruptly 
with  muscular  fibre ;  but  this  is  not  the  case, 
for  tendinous  fibres  are  distributed  over  the 
whole  muscle,  crossing  it  diagonally  in  both 
directions,  so  as  to  form  a  double-spirally 
extensible  sheath  ;  the  tendinous  fibre  finally 
collects  at  the  extremity  of  a  muscle,  and 
forms  the  tendon. 

Each  muscle  is  surrounded  by  cellular 
membrane,  which  dips  into  its  substance, 
and,  by  means  of  the  fat  which  its  cells  con- 
tain, lubricates  the  parts,  and  thus  guards 
against  friction. 


A  TABLE  OF  THE  NAMES  AND  NUMBER  OE  MUSCLES,  DIVIDED  INTO  REGIONS. 


SUBCUTANEOUS  REGION  (BENEATH  THE  SKIN). 

1.  Panniculus  carnosus. 

AURICULAR  REGION   (MUSCLES  OF  THE  EAR). 

2.  AttoUentes  maximus. 

3.  AttoUentes  anterior. 

4.  AttoUentes  posterior. 
0.  Anterior  conchse. 

6.  Posterior  conchae. 

7.  Retrahentes  extemus. 

8 


8.  Retrehentes  internus. 

9.  Abducens  vel  deprimens  aurem. 

PALPEBRAL    REGION   (MUSCLES  OF   THE    EYELIDS). 

10.  Levator  palpebrce  superioris. 

11.  Orbicularis  palpebrarum. 

OCULAR  REGION   (MUSCLES  OF  THE  EYE). 

12.  Levator  palpebrae  superiorus  internus. 

13.  Levator  oculi. 

(57) 


58 


ANATOMY   AND   PHYSIOLOGY   OF 


14.  Depressor  oculi  internus. 

15.  Abductor  oculi  cxternus. 

16.  Adductor  oculi  internus. 

17.  Obhquus  superioris. 

18.  Obliquus  inf'erioris. 

19.  Retractor  oculi. 

ANTERIOR  MAXILLARY  REGION   (MUSCLES  OF  THE  NOSE 
AND  FACE). 

20.  Zygomaticus. 

21.  Levator  labii  superioris  aliquae  nasi. 

22.  Dilator  naris  lateralis. 

23.  Nasalis  longus  labii  superioris. 

24.  Caninus  vel  levator  anguli  oris. 

25.  Buccinator. 

26.  De])ressor  labii  inferioris. 

27.  Levator  menti. 

28.  Dilator  narium  anterior. 

29.  Nasalis  bre\is  labii  sujjcrioris. 

30.  Depressor  labii  superioris. 

31.  Orbicularis  oris. 

POSTERIOR  M-iXILL.VRY  REGION  (^^ITSCLES  OF  THE  HE/iD 
AND   CIIEEKS). 

32.  Temporalis. 

33.  Masseter. 

34.  Stylo-maxillaris. 

35.  Pterygoideus  internus. 

36.  Pterygoideus  extern  us. 

nrOIDEAL   REGION  (MUSCLES   BETWEEN  THE   BRANCHES 
OF  TIIE   LOA\'ER  JAW). 

37.  Digastricus. 

38.  Mylo-hyoideus. 

39.  Genio-hyoideus. 

40.  Ilyoideus  magnus. 

41.  Ilyoideus  par^-us. 

42.  Stylo-hyoideus. 

GLOSSAL   REGION   (MUSCLES   OF   HIE   TONGUE). 

43.  Hyo-gloRsus  longus. 

44.  Hyo-glossus  brevis. 

45.  Gcnio-byo-glossus. 

46.  Lingualis. 

PILVRYNGLVL   REGION. (MUSCLES  ABOUT  THE   PILVRYNX). 

47.  Hyo-pharyngeus. 

48.  Palato-pharyngeus. 

49.  Stylo-jjliaryngeus. 

49^.  Constrictor  pharj'ngis,  anterior. 

50.  Constrictor  pharyngis,  medius. 

51.  Constrictor  pharyngis,  posterior. 

LARYNGE.U,    REGION    (MUSCLES   ABOUT    TUE   LARYN'X). 

52.  Ilyo-thjToideus. 

53.  Crico-thjToideus. 

54.  Crico-arytenoideus  posticus. 

55.  Crico-aiytenoideus  lateralis. 

56.  ThjTO-antcnoidcus. 

57.  Ai-ytenoidcus. 

58.  Hyo-cpiglottideu8. 


PALATEST:  REGION  (MUSCLES  OF  THE  PALATE). 
69.  Tensor  palati. 

60.  Circumflexus  palati. 

MUSCLES  OF  TIIE  NECK. 

nUMERO-CERVICAL  REGION  (MUSCLES  SITUATED  ON  THE 
UPPKR   AND   LOWER   PARTS    OF   THE  NECK). 

61.  Khomboideus  longus. 

62.  Levator  humeri. 

LATERAL    CER^^C.VL   REGION    (SIDE    OF  THE  N'ECK). 

63.  Splenius. 

64.  Complexus  major. 

65.  Trachclo-mastoideus. 

66.  Spinalis  colli. 

SUPERO-CERVICO-OCCIPIT.VL  REGION  (MUSCLES  SITUATED 
ABOVE   THE  HEAD). 

67.  Complexus  minor. 

68.  Rectus  ca])itis  posticus,  major. 

69.  Rectus  capitis  j)osticus,  minor. 

70.  Obliquus  cajjitis,  superior. 

71.  Obliquus  capitis,  inferior. 

INTERIOR    CERMCAL     REGION    (MUSCLES    SITU.ATED     IN 
THE   ANTERIOR   PART  OF  THE  NECK). 

72.  Stcrno  maxillai'is. 

73.  Sterno-thyro-hyoideus. 

74.  Subscapulo-hyoideus. 

75.  Scalenus. 

76.  Longus  colli. 

INFERIOR    CERVICO-OCCIPIT.VL     REGION    (MUSCLES    BE- 
NE^VTH   THE   BASE  ATLAS). 

77.  Rectus  capitis  anticus,  major. 

78.  Rectus  capitis  anticus,  minor. 

79.  Obliquus  capitis,  anticus. 

:\IUSCLES  OF  THE  CHEST. 

DORSO    SaVPULAR    REGION    (MUSCLES    SITUATED  ABOUT 
THE   SHOULDER   BLADE). 

80.  Trapezius. 

81.  LatissimuR  dorsi. 

82.  Rhomboidcus  bre\is. 

PECTORAL    REGION    (MUSCLES   SITUATED    IN    FRONT  OF 
THE  BREAST  BONE). 

83.  Pectoralis,  transversus. 

84.  Pectoralis,  magnus. 

85.  Pectoralis  paruis. 

COSTAL    REGION    (MUSCLES   SITUATED    EXTERNAL    AND 
INTERNAL   TO  THE  RIBS). 

86.  Serratus  magnus. 

87.  Intercostales  externi. 

88.  Intercostales  interni. 

STERNi^a  REGION   (MUSCLES  OF  THE  BREAST  BONTE). 

89.  Lateralis  sterni. 

90.  Sterno-costalis,  externi. 

91.  Sterno-costalis  interni. 


THE    HORSE. 


59 


DOE,SO-COST.\L    REGION     (MUSCLES    ON    THE   SIDES  AND 
UPPER   PART  OF   THE   CHEST). 

92.  Superlicialis  costarum. 

93.  Transversalis  costarum. 

94.  Levatores  costarum. 

DORSAL   REGION   (MUSCLES   OF  TIEK   BACK,  .ANTERIOR  TO 
THE    LUMBAR   \T;RTEBR.E). 
06.  Longissimus  dorsi. 

96.  SjAualis  dorid. 

97.  iSemi  spinalis  dorsi. 

DIAPHR-VGJIATIC   REGION. 

98.  Diaphragm  or  midrilf. 

MUSCLES  OF  THE  ABDOMEX. 

LUMBAR    REGION    (MUSCLES   OF   THE   LOINS). 

99.  Semi  sjdnalis  lumborum. 

100.  Intertransversales  lumborum. 

101.  Sacro  lumlftiiis. 

102.  Psoas  Magnus. 

103.  lliacus. 

104.  Psoas  parvus. 

ABDOMINAL   REGION    (MUSCLES   OF   THE  ABDOMEN). 
10.5.  Obliquus  externus  abdominis. 
lOG.  Obliquus  interniis  abdominis. 

107.  Transvei'saiis  abdominis. 

108.  Rectus  abdominis. 

ANAL    REGION    (MUSCLES   OF   THE  ANUS). 

109.  Retractor  ani. 

110.  Spliincter  ani. 

GENITAL    REGION    (MUSCLES   OF   THE    M.\I,E   ORGANS  OF 
GENERATION). 

111.  Cremaster. 

112.  Erector  penis. 

113.  Triangularis  penis. 

114.  Accelerator  urinse. 

The  muscles  ui  the  genital  regions  of  the  female  are 
named  :  Erector  CUtoridis,  Spliincter  Vaginae. 

COCCYGEAL   REGION   (MUSCLES   OF  THE  TAIL). 

115.  Erector  coccygis. 

116.  Depressor  coccygis. 

117.  Curvator  coccygis. 

118.  Compressor  coccygis. 

MUSCLES  OF  THE  FORE  EXTREMITIES. 

EXTERNAL   SCAPULAR    REGION   (MUSCLES    ON   THE  OUT- 
SIDE   OF   THE  SHOULDER  BLADE). 

119.  Antea-spinatus. 

120.  Portea-spinatus. 

INTERNAL   SCIPULAR    REGION    (MUSCLE   ON  THE  INSIDE 
OF   SHOULDER  BLADE). 

121.  Subscapularis, 

POSTERIOR    SCAPULAR    REGION    (MUSCLES    BEHIND  THE 
SHOULDER  BLADE). 

122.  Teres  major. 

123.  Teres  minor. 


ANTERIOR    HUMERAL    REGION   (MUSCLES   IN    FRONT    OF 
THE   OS   HUMERI). 

124.  Coraco-humeralis. 
12o.  Flexor  bracliii. 
126.  llumcralis  externus. 

POSTFJIIOR    HUMERAL    REGION    (MUSCLES     BEHIND   THE 
OS    HUMERI). 

Ca])ut  magnum. 
Caput  medium. 
Caput  parvum. 
Anconeus. 

MUSCLES  OF  THE  ARM  AXD  FORE  LEG. 

ANTERIOR  BRACmO  CRUR.AL  REGION  (MUSCLES  IN  FRONT 
OF   niE   ARM). 

131.  Extensor  metacarpi  magnus. 

132.  Extensor  pedis. 

133.  Extensor  sutlraginis. 

134.  Extensor  metacarpi  obliquus. 

SLTERFICIAL     POSTERIOR     BRACHIO     CRURAL     REGION 
(MUSCLES   ON   Tim    EXTERNAL   SIDE   OF   THE   ARM). 

135.  Flexor  metacarpi  externus. 

136.  Flexor  metacarpi  medius. 

137.  Flexor  metacarpi  internus. 

138.  Flexor  accessorius  sublimis. 

DEEP    POSTERIOR    BRACHIO    CRLT..\L     REGION.      (THESE 
MUSCLES   ARE   SITUAlTiD   BENEATH  THE  FORMER.) 

139.  Flexor  pedis  perforatus. 

140.  Flexor  pedis  perforans. 

141.  Flexor  pedis  accessorius  profundus. 

142.  Lumbrici,  anterior. 
142^.  Lumbrici,  posterior. 

MUSCLES  OF  THE  HEVD  EXTREMITIES. 

GLUTEAL    REGION   (JIUSCLES    OF     THE   SUPERIOR    PART 
OF   THE   QUARTER). 

143.  Gluteus  externus. 

144.  Gluteus  maximus. 

145.  Gluteus  minimus. 

PEL"S^-TROCHANTERIAN   REGION  (JIUSCLES   SITUATED   AT 
THE   UPPER   PART  OF   THE  THIGH   BONE). 

146.  Pjriibrrais. 

147.  Obtm-ator  externus. 

148.  Obturator  internus. 

149.  150.  Gemini. 

ANTERIOR    ILIO-FEMORAL    REGION    (MUSCLES  SITUATED 
AT  THE   FORE   PART  OF  THE  lULTCCU). 

151.  Tensor  vagiuae. 

152.  Rectus. 

153.  Triceps  vasti. 

154.  Rectus  parvus. 

INTERNAL   HIO    FEMORAL   REGION    (MUSCLES    SITUATED 
AT  THE   ISKER  PART  OF  THE  HAL'NCH). 

155.  Sartorius. 


60 


ANATOMY   AND   PHYSIOLOGY   OF 


156.  Gracilis. 
lol.  Pcctiiifus. 

158.  «  o  C  Adductor  brevis. 

159.  1 1  ^  Adductor  loiigus, 
IGO.  t^l  C  Adductor  magniis, 

POSTEKIOR    ILIO    FEMORAL    REGIOX    (MUSCLES   OX  THE 
OUTER  AND  POSTERIOR  P.VRT  OF  THE  HAUNCH). 

161.  Biceps  abductor. 

162.  Abductor  tibialis. 

MUSCLES  OF  THE  THIGH  AND  LEG. 

ANTERIOR  AST)  FEMERO-CRUEAL    REGION  (MUSCLES    IN 
FRONT  OF  THE  TIBIA). 

1G3.  Extensor  pcilis. 

164.  Peroneus. 

165.  Flexor  metatarsi. 

SUPERFICLVL     POSTERIOR     FEMORO-CRURAL     REGION 
(MUSCLES  IN  THE  REGION  OF  THE  HOCK). 

166.  Gastrocnemius  externus. 

167.  Gastrocnemius  internus. 

168.  Plantaris. 

DEEP    POSTERIOR    FEMORO-CRURAL    REGION    (MUSCLES 
WHICH  ARE  FOUND  BENEATH  THE  FORMER). 

169.  PoiDliteus. 

170.  Flexor  pedis. 

171.  Flexor  pedis  accessorius. 

The  muscles  of  the  internal  ear  are  named : 

Laxator  tympani, 2 

Membrana     " 2 

Tensor  " 2 

Stapedius,  2 

Total,  8 

RECAPITULATION. 

"We  shall  now  recapitulate,  as  regards 
what  has  preceded,  in  reference  to  the  num- 
ber of  muscles;  for  there  exist  various 
opinions  regarding  the  same.  It  may  be 
proper  for  us  to  bear  in  mind,  however,  that 
VETERINARY  SCIENCE,  here,  is  yet  in  its  in- 
fancy ;  and  it  is  well  known  to  some  prac- 
titioners, that  there  are  several  muscles 
which  remain  to  be  named  by  some  future 
compiler  of  veterinary  literature.  But  for 
all  practical  purposes  we  know  enough  of 
the  anatomy  of  the  horse.  The  industrious 
individual,  however,  who  not  only  desires  to 
make  himself  conversant  with  what  is  al- 
ready Imown,  but  aims  to  improve  in  the 


future,  will  not  rest  satisfied  with  the  pro- 
ductions of  his  predecessors.  To  such  an  one 
we  bow  with  due  deference,  and  encourage 
hnn  to  proceed  in  the  work  of  progression. 
There  is  a  fine  field  for  exploration,  and  a 
discerning  public  are  ready  and  willing  to 
crown  the  industrious  laborer  with  the  laurel 
of  merit. 

In  the  preceding  table,  the  number  of 
muscles,  including  those  marked  49  1-2  and 
142  1-2,  appears  to  be  173;  among  these 
are  ten  single  ones,  which  are  thus  expressed: 


Whole  number. 
Deduct  single  ones, 

Pau-s,   . 


]\Iultiply  by 


173 
10 

163 

2 


Single  muscles, 326 

Add  muscles  of  the  internal  ear,  four  pairs,       8 

334 

Single  muscles,  as  above  added,        .        .      10 

344 

It  appears,  therefore,  that  there  are  in  the 
system  of  the  horse  three  hundred  and  forty- 
four  muscles. 

It  should  be  borne  in  mind,  that  in  the 
preceding  classification  all  are  considered  as 
muscles.  Among  them  are  found  tendons, 
which  are  component  parts,  or  rather  ap- 
pendages, to  the  same.  Mr.  Percivall  says 
there  are,  in  the  horse,  151  pairs,  and  10 
single  muscles ;  add  the  four  pairs  of  the  in- 
ternal ear,  which  he  has  omitted  in  the  cal- 
culation, and  we  get  155  pairs.  On  page 
72,    "  Hippapathology,"     the     number    of 

muscles  is 

312 

Add  muscles  of  the  ear,  omitted,     .         .         8 


The  author's  estimate. 


320 
344 

24 


Difference, 

Probably  the  above  author  considers  the 
"  24  "  as  tendons. 


EXPLANATION   OF  FIGURE  VII. 


NO.    1.  — OSSEOUS   STRUCTUEE. 


35. 

Radius. 

9- 

Trapezium. 

36. 

Lower  row  of  the  carpal  bones. 

37. 

Metacarpus  magnus. 

38. 

Sessamoids. 

39. 

Os  suffragiais. 

40. 

Os  corona. 

41. 

Os  pedis. 

NO.   2.  —  MUSCULAR  STRUCTURE. 

INTERNAL  VIEW  OF  THE  NEAK-FORE  LEG. 

o".  Pectoralis  transversalis. 

q".  Flexor  metacarpi  medius. 

r".       "  "         intcrnus. 

s".  Extensor  metacarj^i  magnus. 

t"  "  "  obliquus. 

u".  u".  Flexors  pedis  —  perforatus  et  perforans. 

v".  Suspensory  ligament. 

x".  Extensor  pedis. 

z.  8.  Bifurcation  of  the  suspensory  ligament. 

NO.    3. 

The  description  of  No.  1  answers  also  for  No.  3.     The  letter  f.  is  intended  to 
point  out  the  location  of  the  ulnar,  into  wliich  is  inserted  the  triceps. 
g.    Region  of  the  carpus. 

NO.   4. 

n".  Triceps  extensor  brachii. 

o".  Pectoralis  transversalis. 

o'.  P".  Flexor  metacarpi  externus. 

q".  Flexor  metacarpi  medius. 

^t".  Fleshy  belly  of  the  perforatus  et  perforans. 

x".  Extensor  pedis. 

g".  Extensor  suflraginis. 

z".  u".  r".  Flexors  tendons. 

$f.   Hoof. 


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EXPLANATION  OF  FIGURE  VIII. 


NO.   1..- OSSEOUS   STRUCTURE. 

22.  Femur. 

23.  Patella. 

24.  Fibula. 

25.  Os  calcis. 

26.  Astragalus. 

27.  Inferior  row  of  the  tarsal  bones. 

28.  Metatarsus  magnus. 

29.  Sessamoids^. 

30.  Os  suffraginis. 

31.  Os  corona. 

32.  Os  pedis.' 

The  above  explanations  will  serve  to  illustrate  No.  3.     *  *  are  the  matatarsi 
parvium. 

NO.   2. 

INSIDE   YIEW  OF  THE-OFF-IliPfD  LEG. 

(/.     Rectus. 

p'.  Vastus  internus. 

q'.  X.  X.  Extensor  jjedis. 

q.     Flexor  metatarsi. 

r'.  v'.  Gastrocnemius  externus  et  internus. 

t.     Peroneus. 

u.    The  insertion  of  the  gastrocnemi. 

v'.  V.  Tendon  of  the  flexor  metatai'si. 

z\    Suspensory  ligaments. 

Sf.    The  hoof. 

5.  5.  The  saphena  vein. 

K.  Abductor  femoris. 

8.    Bifurcation  of  the  suspensory  ligament. 

u'.  (Beneath  the  postern)  Perforatus  et  perforans. 

NO.    4. 

K.  J.  Biceps,  showing  the  manner  in  wliich  it  bifurcates. 

r'.    Gastrocnemius  internus. 

f.     Peroneus. 

v'.    Flexor  pedis  accessorius. 

5.         "  "      externus. 

u'.    Insertion  of  the  gastrocnemi. 

y'.    Peroneus. 

u.  ii\  v'.  Flexors  of  the  foot. 

^.    The  hoof. 


THE   HOESE. 


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ANATOMY  AND   PHYSIOLGOT   OF   THE   HORSE. 


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ON    DISSECTION. 


No  man  can  ever  expect  to  become  a 
practical  anatomist  or  pathologist,  unless 
he  practise  dissection.  It  is  the  only  possi- 
ble way  by  which  he  can  familiarize  him- 
self with  the  healthy  structural  organiza- 
tion of  the  horse.  Having  made  himself 
acquainted  with  the  healthy  aspect  of  the 
various  parts,  their  uses,  etc.,  he  next  is 
able  to  judge  of  the  various  grades  of 
textural  change  Vviiich  occur  and  exist, 
between  the  part  that  has  been  studied 
under  its  healthy  aspect,  and  that  which 
has  now  departed  from  its  healthy  con- 
dition. Thus,  in  the  prosecution  of  the 
study  of  anatomy,  the  student  finally  be- 
comes a  pathologist ;  and,  although  he  may 
be  a  beginner,  he  places  himself  in  a  posi- 
tion only  a  few  removes  from  the  old  and 
experienced  practitioner,  and  can  venture 
to  "  measure  a  lance  "  with  the  renoiuned 
knights  of  the  healing  art. 

DISSECTING    INSTRUMENTS. 

The  dissector  should  supply  himself  with 
a  beak-pointed  scalpel  (which  is  one  of  Ger- 
man origin),  for  superficial  dissection,  and 
a  myology  knife,  strong  and  rounded  at  its 
point.  For  the  dissection  of  blood-vessels 
and  nerves,  a  more  delicate  and  pointed 
scalpel  is  needed.  The  forceps  should  be 
strong,  and  armed  at  the  points  with  teeth ; 
two  pair  of  scissors  are  needed,  one 
pointed  and  the  other  blunt ;  a  saw  and 
blunt  chisel,  for  opening  the  cranium.  A 
blow-pipe,  curved  needles,  and  a  few  extra 
scalpels,  are  all  that  the  student  requires. 

SUBJECTS    SUITABLE    FOR    DISSECTION. 

For  demonstration  of  the  muscular  sys- 
tem, a  well-proportioned  and  fully-developed 
subject  should,  if  possible,  be  selected,  and 


one  that  has  died  suddenly,  or  been  killed 
in  consequence  of  some  accident,  is  to  be 
preferred.  For  making  wet  and  dry  prepa- 
rations, lean,  emaciated  subjects  should  be 
selected.  The  lymphatic  system  is  best 
shown  on  animals  of  a  flabby  and  cedema- 
tous  organization.  Young  animals  are  the 
best  subjects  for  dissection,  in  view  of  de- 
monstrating the  circulatory  and  nervous 
systems. 

RULES  IN  REFERENCE  TO    DISSECTION  OF  THE 

MUSCLES.. 

As  there  are  abundance  of  subjects  to  be 
had  in  the  United  States,  and  it  being  in- 
convenient for  one  individual  to  dissect  a 
whole  subject,  he  had  better  divide  it  into 
six  parts,  viz. :  1st,  The  head  and  neck. 
2nd  and  3rd,  The  anterior  extremities, 
wliich  include  the  thorax,  its  contents,  and 
the  diaphragm.  4th'  and  5th,  The  poste- 
rior extremities,  to  which  belong  the  pelvic 
and  abdominal  viscera.  6th,  Those  viscera 
which  cannot  be  advantageously  divided, 
as  the  heart,  stomach,  bladder,  organs  of 
generation,  &c.  Should  the  dissector  de- 
cide to  commence  on  the  lohole  subject,  he 
first  removes  the  sldn,  in  order  to  expose 
the  panniculous  carnosus  ;  this  will  require 
some  care,  as  some  of  the  fibres  of  this 
subcutaneous  muscle  are  intimately  con- 
nected with  the  former.  There  are  various 
ways  of  removing  the  skin :  the  author  pre- 
fers to  commence  on  the  back,  and  dissect 
off  towards  the  feet.  Supposing  th^  sub- 
ject to  lie  on  the  off"-side,  we  commence  an 
incision  at  the  anterior  part  of  the  nasal  re- 
gion, and  continue  the  same  upward  until 
we  arrive  at  the  occiput  ;  we  then  in- 
cline the  scalpel  from  the  superior  part  of 
the  neck,  in  order  to  avoid  the  mane,  and 

(70) 


80 


ANATOMY   AND    PHYSIOLOGY   OF 


continue  the  incision  along  the  lateral  part 
of  ihc  dorso  lumbar  spines  until  the  coccyx 
is  reached;  the  overlapping  portion  can 
then  be  dissected,  and  turned  over  to  the 
off-side,  so  as  to  expose  the  tendinous  in- 
sertions of  the  panniculus  into  the  ligamcn- 
tum  nucha),  etc.,  etc.  The  panniculus  being 
exposed,  it  may  be  divided  into  three  parts, 
viz.:  1st,  The  Cervical  portion,  which,  com- 
prises the  head,  neck,  shoulders,  and  fore- 
arms. 2nd,  The  Thoracic  portion.  3rd, 
The  Abdominal  portion. 

Having  traced  the  attachments  of  the 
panniculus,  the  muscles  then  engage  our 
attention ;  they  being  composed  of  nearly 
parallel  fibres,  the  manner  of  displaying 
them  is  indicated.  The  cellular  tissue 
should  if  possible  be  detached  with  the 
sldn  and  panniculus  ;  without  this  precau- 
tion the  surface  of  some  of  the  coarser 
muscles  would  have  a  mangled  appearance. 
The  knife  should  always  follow  the  dnec- 
tion  of  the  muscular  fibres,  and  the  part  on 
which  a  muscle  is  to  be  dissected  should  be 
placed,  if  possible,  in  such  a  situation  as  to 
produce  a  forcible  extension  of  that  muscle ; 
thus,  in  tracing  the  origin  and  insertion  of 
a  muscle,  the  dissector  becomes  acquainted 
with  its  use. 

After  exposing  the  external  layer  of  mus- 
cles they  may  be  detached  from  their  in- 
sertion, or  divided  in  their  centre  ;  if  di- 
vided, we  thus  preserve  the  two  points  of 
origin  and  insertion.  The  deeper  seated  mus- 
cles may  be  demonstrated  in  the  same  way. 

In  the  dissection  of  muscles  the  scalpel 
should  be  used  in  a  free  and  prompt  man- 
ner ;  the  strokes  should  be  long  and  bold, 
using  the  little  finger  to  steady  the  move- 
ment of  the  hand.  In  maldng  autopsies 
and  in  examining  the  viscera,  the  subject  is 
generally  placed  on  his  back. 

ANATOMICAL  PREPARATIONS. 

It  is  highly  important  that  every  student 
should  be  acquainted  with  the  methods  of 
maldng  wet  and  dri/  preparations,  and  of 
injecting  the  blood-vessels ;  for  specimens 
of  this  Idnd  are  the  best  means  of  familiar- 
izing us  with  the  structures  of  quadrupeds, 


and  such,  when  properly  prepared,  possess 
a  real  and  practical  value. 

INJECTING    INSTRUMENTS. 

Pole  describes  three  kinds  of  instruments 
used  in  making  injected  preparations. 

The  first  consists  of  a  brass  syringe, 
made  of  various  sizes ;  the  nozzle  is  adapted 
to  pipes  into  which  the  syringe  is  to  be  in- 
serted ;  a  short  pipe,  with  stop-cock,  also 
accompanies  the  syringe,  which  is  to  be 
applied  between  the  syringe  and  either  of 
the  pipes. 

The  second  is  a  similar  instrument,  only 
much  smaller ;  its  pipe  is  very  minute,  and 
its  piston  is  fm*nished  with  a  ring,"  so  that 
the  thumb  may  be  used  to  throw  its  con- 
tents into  a  vessel. 

The  third  instrument  is  generally  used 
for  injecting  the  glands  and  lymphatics  with 
quicksilver.  It  consists  of  a  glass  tube, 
terminating  with  a  steel  end,  and  having  an 
extremely  fine  steel  pipe,  which  screws  on 
to  the  latter.  The  syringe  used  by  the 
author  of  this  work  is  one  manufactured  in 
England  (and  can  be  found  in  some  of  our 
agricultural  stores),  for  the  purpose  of  sjn:- 
inging  plants ;  it  has  the  most  accurate 
bore  and  finely-adjusted  piston  of  any  in- 
strument now  in  use,  and  being  of  medium 
size  it  can  be  used  for  either  large  or  minute 
injections.  Some  alterations,  however,  have 
to  be  made  in  the  nozzle  and  pipes  fitted 
accordingly. 

DIRECTIONS    FOR    USING    THE    SYRINGE. 

In  using  the  syringe,  a  certain  amount  of 
tact  or  experience  is  necessary,  and  the  be- 
ginner must  not  feel  disappointed  should  he 
fail  in  a  first  or  second  attempt ;  for  some 
little  oversight  might  frustrate  the  whole 
process.  Everything  should  be  in  readiness, 
such  as  ligatures,  forceps,  scissors,  sponge, 
hot  and  cold  water,  etc. 

The  pipes  should  be  inserted  into  the  ves- 
sels, and  confined  there  by  strong  ligatures; 
and,  before  the  syringe  is  inti'oduced,  its  noz- 
zle must  be  turned  upwards,  and  the  piston 
pressed  until  all  the  air  and  froth  are  ejected ; 
then  introduce  the  nozzle  into  the  stop-pipe 


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^^^"^   ^'^%< 


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EXPLANATION   OF   FIGUEE    !X. 


OSSEOUS   STPJ 

i. 

Frontal  bones. 

2. 

Parietal. 

3. 

Occipital. 

4. 

Temporal. 

5. 

Nasal. 

6. 

Lachrpnal. 

7. 

Malar. 

8. 

Superior  maxillarius. 

9. 

Anterior          " 

10. 

Inferior            " 

11. 

Cervical  vertebrae. 

16. 

The  true  ribs. 

18. 

The  sternum. 

33. 

The  scapula. 

34. 

The  humerus. 

c. 

The  incisors. 

d. 

Dorsal  spines. 

MUSCULAR  STRUCTURE. 

ANTEHIOK  VIEW. 

a".  Trapezius. 
c".    Scalenus, 
e".    Pectoralis  parvus. 
f".  Antea  spinatus. 
g".  Postea  spinatus. 
Ti".  Teres  major. 

v.    A  portion  of  the  triceps  extensor  brachii. 
8.    The  faschial  covering  of  the  splenius. 
K.  The  masseter. 
g.    Levator  labii  superioris. 
f.    Nasalis  longus. 
e.     Orbicularis  oris. 

c.  Dilator  narium  lateralis. 

d.  Dilator  narium  anterior. 

m.  I.  Attolentes  et  abducens  aurem. 

h.  Levator  palpebra?. 

a.  Orbicularis  palpebrarum. 

o".  Pectoralis  transversahs. 

u.  Levator  humeri. 

V.  Sterno  maxillaris. 

X.  Subscapulo  hyoideus. 

2.  Maxillary  vein. 

3.  Jugular  vein. 


THE   HORSE. 


81 


and  press  the  piston  steadily  until  a  sensible 
resistance  is  felt.  If  much  force  be  used, 
rupture  of  a  vessel  may  take  place.  After 
a  prudent  force  has  been  applied  for  some 
time,  the  syringe  may  be  withdrawn,  pre- 
viously securing  the  stop-cock.  A  steady 
and  uniform  pressm-e  on  the  piston  will  be 
more  likely  to  secure  uniform  injection  than 
force,  or  sudden  jerks.  Should  the  first  in- 
jection fail  to  fill  the  vessels,  it  must  be 
immediately  followed  by  a  second.  When 
injecting  through  a  very  small  pipe,  the  in- 
jector must  be  patient,  and  steadily  con- 
tinue the  pressure  on  the  piston. 

When  using  ivarm  injections,  the  syringe 
must  be  kept  luarm  by  immersing  it  in  hot 
water,  and  the  part  to  be  injected  must  also 
be  kept  at  the  same  temperature,  by  the 
same  means. 

DIFFERENT  KINDS  OF  INJEC- 
TIONS. 

There  are  six  kinds  of  injections  now  in 
use,  viz.,  the  cold,  coarse,  and  fine  injection, 
the  minute,  the  mercurial,  and,  finally,  the 
plaster  of  Paris  injection.  The  five  first 
are  most  employed  ;  the  plaster  of  Paris  is 
objectionable  because  it  is  easily  firactured. 

FORMULA      FOR     COARSE     WARM     INJECTIONS. 

Red. — Beeswax,  sixteen  ounces;  white 
resin,  eight  ounces ;  turpentine  varnish,  sLx 
ounces  ;  vermilion,  three  ounces. 

First  liquify  the  wax,  resin,  and  turpen- 
tine varnish,  in  an  earthen  pot,  over  a  slow 
fire,  or  in  a  water  bath ;  then  add  the  Ver- 
million, previously  reducing  it  to  a  fine 
powder,  so  that  the  coloring  ingredients 
may  be  intimately  and  smoothly  blended, 
then  add  the  same  to  the  above  ingredients, 
and,  when  they  have  accrued  due  heat,  the 
injection  is  fit  for  immediate  use. 

Yellow  Injection.  —  Take  beeswax,  eight 
ounces ;  resin,  four  ounces ;  turpentine  var- 
nish, three  ounces ;  yellow  ochre,  one  ounce 
and  a  quarter. 

While     Injection.  —  Clarified     beeswax, 
eight  ounces ;    resin,  four  ounces ;   turpen- 
tine varnish,  three  ounces ;  flake  white,  two 
ounces  and  a  quarter. 
11 


Pale  Blue  Injection.  —  Take  the  preced- 
ing ingredients,  and  add  to  them  a  small 
portion  of  indigo. 

Black  Injection.  —  Beeswax,  resin,  and 
turpentine  varnish  in  the  above  proportions ; 
and  add  lamp-black  ad  libitum. 

The  same  rules  are  to  be  observed  in  pre- 
paring all  the  injections. 

FORMULiE    FOR    FINE  INJECTIONS. 

Red.  —  Brown  and  white  spirit  varnishes, 
of  each  four  ounces ;  turpentine  varnish, 
one  ounce ;  vermilion  one  ounce. 

Yellow. — Brown  and  white  spirit  varnishes, 
of  each  four  ounces  ;  turpentine  varnish,  one 
ounce  ;  king's  yellow,  one  ounce  and  a  half. 
To  make  a  white  injection,  add  to  the  last 
formula  two  ounces  of  flake-white  instead 
of  king's  yellow. 

Blue.  —  Brown  and  white  spirit  varnishes, 
of  each  four  ounces  ;  turpentine  varnish,  one 
ounce ;  Prussian  blue,  one  ounce  and  a 
half.  This  may  be  made  black  by  adding 
ivory  black  instead  of  Prussian  blue. 

FORMULiE    FOR    MINUTE    INJECTIONS. 

The  liquifying  principle  in  minute  injec- 
tions is  "  5ice,"  which  is  made  in  the  fol- 
lowing mamier : 

Take  fine  transparent  glue,  one  pound, 
break  it  into  pieces ;  put  it  into  an  earthen 
pot,  and  pour  on  it  three  pints  of  cold  water ; 
let  it  stand  twenty-four  hours,  stirring  it 
occasionally  with  a  stick ;  then  set  it  over  a 
slow  fire  until  it  is  perfectly  dissolved  ; 
skim  off  all  the  scum  from  the  surface,  and 
strain  the  remainder  through  flannel  ;  it 
will  then  be  fit  for  the  coloring  ingredients. 

Minute  Red  Injection.  —  Size,  one  pint ; 
vermilion,  three  ounces  and  a  half. 

Yellow.  —  Size,  one  pint ;  king's  yellow, 
two  ounces  and  a  half. 

White.  —  Size,  half  a  pint  ;  flake  white, 
one  ounce  and  three  quarters. 

Blue.  —  Size,  half  a  pint  ;  fine  blue  smalt, 
six  ounces. 

PLASTER    INJECTION. 

Before  mixing  the  plaster  of  Paris,  the 
pipes  must  be  secured  to  the   mouths  of 


82 


ANATOMY    AND    PHYSIOLOGY   OF 


the  vessels  at  which  the  injection  is  to 
enter.  Plaster  of  Paris  (to  which  some 
of  the  preceding  dry  coloring  materials, 
suitable  to  the  fancy,  can  be  added)  must 
be  put  in  a  mortar  and  rubbed  with  a 
pestle  in  order  to  pulverize  it  completely ; 
water  is  then  to  be  added  until  the  mixture 
is  of  the  consistence  of  cream ;  the  syringe 
being  in  readiness,  it  is  to  be  filled  and  im- 
mediately injected  into  the  vessels.  In  the 
author's  opinion,  this  injection  is  only  suit- 
able for  injecting  first-class  vessels,  for  it 
coagulates  or  "se^s"  so  quickly  that  it 
cannot  be  used  as  a  minute  injection.  It  is 
said  that  a  small  quantity  of  olive  oil,  in- 
corporated with  the  liquid  plaster,  retards 
its  coagulation  ;  yet  if  too  much  were 
added  it  would  spoil  the  preparation. 

The  moment  the  parts  are  injected  the 
syringe  should  be  washed  out  in  cold 
water,  and  when  the  injection  "sc^s"  in 
the  veins,  the  pipes  must  be  removed  and 
likewise  cleansed. 

FORMULiE    FOR  COLD    INJECTIONS. 

Dr.  Parsons  recommends,  for  coarse  cold 
injections,  the  following  formula :  Take 
coloring  matter  and  grind  it  in  boiled  lin- 
seed oil,  on  a  painter's  marble,  until  it  has 
acquired  the  consistence  of  common  white 
lead,  as  sold  at  the  stores.  After  being 
finely  legivated,  a  little  lime-water,  in  pro- 
portion of  two  table-spoonsful  to  a  pint,  is 
to  be  incorporated  by  stirring.  At  the  mo- 
ment of  filling  the  syringe  with  the  injec- 
tion, there  should  be  added  to  it  about  one- 
third  of  its  measure  of  Venice  turpentine, 
which  should  be  stirred  in  briskly  and  used 
immediately,  as  it  very  soon  hardens. 

For  a  temporary  cold  coarse  injection, 
white  lead  ground  in  oil  answers  every 
purpose ;  it  requires  no  addition  of  lime- 
water,  because  the  lead  is  generally  adul- 
terated with  carbonate  of  lime,  which 
hardens  the  mixture,  and  it  can  be  colored 
to  suit  the  taste,  or  the  vessels  can  be 
colored  with  a  pencil  brush,  before  varnish- 
ing. 

For  filling  the  arteries,  to  dry  and  pre- 
serve, red  lead   is   the   best   and  cheapest 


material ;    vermilion,    however,    resembles 
more  the  color  of  arterial  blood. 

Whatever  part  we  expect  to  inject  with 
warm  injections,  must  be  immersed  in  water 
very  hot, — not  hot  enough,  however,  to  crisp 
the  vessels.  Attention  to  this  matter  is 
highly  important,  in  view  of  successful  in- 
jection. 

THE    COURSE    OF    INJECTIONS. 

Injections  must  follow  the  course  of  the 
circulation ;  the  arteries,  however,  having 
no  valves,  are  easily  injected  in  any  direc- 
tion ;  but  the  veins  are  furnished  with  nu- 
merous valves,  which  prevent  the  flow  of 
injection  from  the  heart.  Sometimes  it  is 
necessary  to  break  these  valves  by  means 
of  a  small  whalebone  probang.  In  the 
region  of  valves  are  often  found  coagula- 
tions, which  must  be  washed  out  before  the 
injection  can  be  introduced ;  and  this,  also, 
must  be  performed  in  the  direction  of  the 
circulation.  Small  pipes  are  to  be  intro- 
duced, and  warm  water  must  be  thrown  in, 
which  can  be  made  to  escape  through  an 
incision  made  with  a  lancet  in  a  region  ap- 
proaching the  right  auricle.  The  incision 
can  afterwards  be  closed  by  suture,  or 
otherwise.  Many  of  the  veins  of  the 
horse,  however,  are  destitute  of  valves,  and 
therefore  admit  of  injection  in  a  direction 
contrary  to  their  circulation. 

To  inject  a  portion  of  the  animal,  —  the 
knee  or  hock,  for  example,  —  it  is  necessary 
to  secure  all  the  branches  of  the  vessels  that 
have  been  divided  where  it  is  separated 
from  the  body.  The  part  is  then  to  be  in- 
jected in  the  same  manner  as  if  we  were 
injecting  the  whole  body. 

QUICKSILVER    INJECTION    AND    PREPARATIONS. 

The  fluid  specific  gravity  and  beautiful 
metallic  lustre  of  quicksilver  render  it  val- 
uable for  displaying  minute  vessels.  Dr. 
Parsons  remarks  that  the  principal  objec- 
tion to  its  general  use  is  the  continuance  of 
its  fluidity,  which  renders  dissection,  after 
injection,  almost  impracticable.  Yet  there 
are  some  very  fine  specimens  of  quicksilver 
injections  of  glands  and  deep-seated  lym- 


THE   HORSE. 


83 


phatics,  in  the  Warren  museum  of  this 
city,  that  cannot  be  surpa-ssed  by  any  other 
kind  of  injection.  The  same  authority  re- 
marks, that  the  specific  gravity  of  quick- 
silver, when  supported  in  a  column,  is  such 
as  to  exert  strong  pressure  upon  a  blood- 
vessel or  lymphatic  that  receives  it,  and 
therefore  in  some  cases  a  syringe  is  unne- 
cessary. It  is  to  be  borne  in  mind  that 
the  force  of  the  injection  depends  upon  the 
perpendicular  height  of  the  column,  and 
not  on  its  diameter,  and  the  former  may  be 
such  as  to  burst  the  vessel.  The  injections 
should  always  be  conducted  in  a  shallow 
dish  or  tray,  so  that  the  quicksilver  may  not 
be  wasted.  When  injecting  the  lym- 
phatics, it  is  necessary  to  be  provided  with 
small  lancets,  straight,  curved,  and  deli- 
cately-pointed fine  needles,  which  must  be 
armed  with  waxed  threads.  For  common 
blood-vessel  preparations,  glass  tubes  of 
the  shape  of  a  straight  blow-pipe  are 
needed. 

INJECTING    THE    LYMPHATICS  WITH    MERCURY 
OR    QUICKSILVER.* 

In  injecting  the  lymphatics,  our  success 
depends,  perhaps,  more  on  the  body  we 
choose,  than  on  any  other  circumstance : 
bodies  slightly  anasarcous,  if  they  be  ema- 
ciated, are  the  best.  From  the  valvular 
structure  of  the  lymphatics,  it  is  necessary 
to  inject  from  the  extremities  towards  the 
trunk. 

It  is  almost  impossible  for  one  person  to 
succeed  in  injecting  the  lymphatics  without 
assistance  ;  there  are  so  many  things  requi- 
site, besides  merely  holding  the  tube  in  the 
vessel,  that  an  assistant  is  indispensable. 

It  is  very  necessary,  before  beginning,  to 
see  that  the  injector  has  within  his  reach 
sharp-pointed  scissors,  knives,  forceps,  lan- 
cets,, pokers  for  tubes,  needles,  and  waxed 
threads,  so  arranged  that  they  can  be  used 
instantly,  for  it  will  often  happen  that  it 
will  be  impossible  for  either  the  assistant 
or  the  operator  to  take  his  eye  for  a  mo- 
ment off  the  vessel,  without  losing  it. 

*  Sir  Charles  Bell. 


When  injecting  the  superficial  lympha- 
tics, we  first  cut  off  a  portion  of  skin,  so  as 
to  expose  the  loose  cellular  texture  ;  having 
found  a  lymphatic  vessel,  it  must  be  seized 
by  the  forceps  and  dissected  from  the  sur- 
rounding substance.  Having  hold  of  it 
with  the  forcep,  snip  it  half  across  with  fine 
scissors,  and  into  the  incision  introduce  the 
tube  containing  the  mercury.  A  poker  or 
director  is  often  necessary  for  the  purpose 
of  creating  a  vacuum ;  a  few  drops  of  mer- 
cury then  introduced  by  the  side  of  the 
director  will  open  the  way  for  more ;  the 
director  being  withdrawn,  the  mercury  flows 
into  the  lymphatics. 

If  the  vessel  to  be  injected  be  a  large 
one,  it  must  be  secured  by  ligature  around 
the  pipe.  The  quicksilver  is  to  be  pressed 
onward,  elevating  or  depressing  the  pipe 
so  as  to  regulate  the  force  of  the  injection. 

In  injecting  a  gland,  we  must  en- 
deavor to  find  the  vessel  that  has  the  most 
influence  in  filling  it.  Having  found  it, 
we  secure  the  other  vessels  and  fill  the 
gland  through  the  former  channel. 

The  vessels  or  glands  injected  with 
mercury  should  be  dried  as  quickly  as  pos- 
sible, and  varnished,  or  else  preserved  in 
spirits  of  turpentine. 

METHOD    OF    INJECTING    THE    LACTEALS. 

Take  a  small  portion  of  the  intestine 
and  mesentery,  and  make  an  incision  in 
one  of  the  most  conspicuous  lacteals,  as 
near  as  possible  to  its  origin  in  the  intes- 
tine ;  then  introduce  the  point  of  the  injec- 
ting tube,  and  conduct  the  operation  agree- 
ably to  the  preceding  rules.  When  the 
quicksilver  flows  out  of  any  of  the  divided 
vessels,  they  must  be  repaired  by  an  assis- 
tant; when  as  many  of  the  lacteals  are 
filled  as  will  receive  the  quicksilver  from 
this  orifice,  introduce  the  pipe  into  another, 
and  repeat  the  process  as  before,  and  so 
on,  until  as  many  of  them  are  fiUed  as  can 
be ;  then  inflate  the  intestine  and  suspend 
it  in  the  air  to  dry,  after  which  it  may  be 
preserved  by  varnishing  both  inside  and 
out. 


84 


ANATOMY   AND   PHYSIOLOGY   OF 


DIRECTIONS      FOR      INJECTING     THE      PAROTID 
GLAND. 

Tliis  should  be  injected  before  removal, 
on  account  of  the  numerous  vessels  by 
which  it  is  attached  to  the  adjacent  parts. 
Before  commencing  the  operation,  the  sldn 
over  the  region  of  the  gland  and  duct  must 
be  raised,  in  view  of  searching  for  the  duct; 
having  found  it,  an  opening  must  be  made 
into  it  with  the  point  of  a  lancet,  suffi- 
ciently large  to  introduce  the  point  of  the 
steel  injecting  pipe  ;  when  introduced,  con- 
fine the  duct  upon  it  by  a  ligatm-e  with  a 
single  knot,  which  shall  serve  when  the 
pipe  is  withdrawn  to  secure  the  quicksilver 
in  the  gland.  The  gland  having  been  filled, 
the  pipe  withdrawn,  and  the  duct  secured, 
we  proceed  with  all  possible  care  to  dissect 
the  gland  from  its  situation.  Any  branches 
of  vessels  going  off  to  suiTounding  parts 
must  be  secured  by  means  of  a  small 
curved  needle,  armed  with  a  single  ligature, 
after  which  they  may  be  divided  with 
safety.  The  gland  being  removed,  and  all 
extraneous  tissue  dissected  off,  it  should  be 
placed  in  water  to  extract  the  blood,  etc. 
This  will  require  about  thirty-six  hours ;  the 
water,  however,  must  be  frequently  changed ; 
the  gland  can  then  be  spread  on  a  piece  of 
pasteboard  and  exposed  to  dry.  It  makes 
the  most  beautiful  preparation,  when  pre- 
served in  a  glass  vessel  containing  pure 
spirits  of  turpentine. 

BREAKING  DOWN  THE  VALVES. 

Many  of  the  glands,  the  surface  of  the  liver 
included,  can  be  injected  contrary  to  the 
circulation  of  the  lymph.  When  the  quick- 
silver passes  at  first  freely  into  the  lympha- 
tics, and  suddenly  stops,  it  will  be  necessary 
to  force  it  forward  by  gentle  pressure  with 
the  edge  of  a  spatula,  in  the  direction  in 
which  it  seems  most  likely  to  run  ;  by  this 
means  the  valves  are  broken  down.  The 
valves  of  the  superficial  lymphatics  of  the 
liver  are  easily  broken  down  in  this  way, 
but  the  valves  in  some  of  the  lymphatics 
are  much  firmer,  consequently  not  so  easily 
broken  down. 


WET   PREPARATIONS. 

PREPARATIONS    BY    DISTENTION. 

Hollow  organs  may  be  distended  for 
preservation  with  antiseptic  liquids,  air, 
wool,  hair,  cotton,  plaster,  quicksilver,  etc. 

Wet  preparations  by  distention^  with 
spirits  of  wine,  oil  of  tm-pentine,  etc. 

The  intention,  in  distending  preparations 
by  spirits,  is  to  give  them  their  natural 
figure,  to  exhibit  more  fully  the  parts  of 
which  they  are  composed,  their  vascularity, 
and  occasionally  some  morbid  or  preter- 
natural appearance. 

METHOD  OF  DISTENDING    AND  PREPARING 
THE    LUNGS. 

The  lungs  taken  from  a  sheep  or  calf 
make  a  very  good  substitute  for  those  of 
the  horse,  which  are  too  bulimy  for  ordinary 
use. 

The  pulmonary  arteries  and  veins  should 
first  be  filled  with  red-colored  injection ;  then 
immerse  the  lungs  in  oil  of  turpentine,  con- 
tained in  a  vessel,  large  enough  to  admit 
them  without  compression;  then  inject  into 
the  trachea  such  a  quantity  of  the  above 
fluid  as  shaU  dilate  them  without  danger  of 
rupture.  Then  secure  the  trachea  by  liga- 
ture. In  the  same  manner  we  proceed  with 
other  parts.  If  a  portion  only  of  an  organ 
or  a  part  of  some  viscera  be  required,  we  fu-st 
secure  the  lower  orifice  by  ligature  ;  inject 
as  above,  and  then  apply  a  ligature  to  the 
upper  opening.  It  can  then  be  suspended 
in  spirits  of  wine  or  turpentine. 

ANTISEPTIC    MENSTRUA  FOR    PRESERVING 

SPECIMENS. 

Alcohol — Spirits  of  Wine.  —  This  is  one 
of  the  principal  fluids  now  in  use  for  the 
preservation  of  specimens.  It  may  be  used 
of  various  strengths,  according  to  the  size 
and  thickness  of  the  specimen  to  be  pre- 
served. 

All  those  that  are  thick  and  bulky  should 
be  put  into  pure  rectified  spirits ;  smaller 
ones  may  require  only  one  half  the  quantity 
of  alcohol  with  water ;  and  such  as  are  thin 


THE   HORSE. 


85 


and  membranous,  can  be  preserved  in  com- 
mon New  England  rum. 

Turpentine. —  This  also  is  an  excellent 
antiseptic,  and  is  highly  recommended  by- 
Parsons  and  others,  for  cartilages,  fibro-car- 
tilages,  and  fibrous  membranes. 

The  acids  used  are,  sulphuric,  nitric,  mu- 
riatic, acetic  and  pyroligneous.  Dr.  Parsons 
states  that  Dr.  Hayden,  surgeon  dentist,  in 
Baltimore,  has  succeeded  in  preserving 
anatomical  preparations  in  a  superior  man- 
ner, with  pyroligneous  acid.  It  should  be 
rectified  and  diluted  with  water.  Acids, 
however,  cannot  be  used  when  the  prepara- 
tion contains  bone. 

METHOD  OF  PRESERVING  THE  BRAIN. 

The  following  mixture  is  a  very  excellent 
menstruum  for  preserving  the  brain  and 
nerves :  Take  alcohol,  eight  parts  by  weight; 
oxymuriate  of  mercury,  one  part.  E-ub  the 
oxymuriate  in  a  mortar,  and  gradually  add 
the  alcohol.  The  brain  should  remain  in 
this  mixture  for  twenty  or  thirty  days,  when 
it  may  be  withdrawn  from  the  liquid,  dried, 
and  varnished. 

METHOD  OF  MAKING    A    DRY  PREPARATION    OF 
THE    AIR-VESSELS    OF    THE    LUNGS. 

Throw  the  lungs  of  a  horse  into  a  barrel 
of  vv^ater  and  allow  them  to  macerate  for 
several  months,  during  the  summer  season ; 
then,  by  repeated  washing,  cleanse  the  bron- 
chia, etc.,  from  the  parenchyma,  dry,  and 
varnish  them. 

METHOD    OF  MACSRATING    AND  CLEANING 
BONES. 

Remove  as  much  of  the  flesh,  ligaments, 
etc.,  as  can  conveniently  be  done  with  the 
knife ;  then  lay  them  in  clean  water,  and 
change  the  same  daily  for  about  a  week,  or 
as  long  as  it  becomes  discolored  with  blood. 
They  are  now  to  remain  without  changing, 
till  putrefaction  has  thoroughly  destroyed 
all  the  remaining  flesh  and  ligaments,  which 
will  take  from  tliree  to  five  months,  more  or 
less,  according  to  the  season  of  the  year  or 
temperature  of  the  atmosphere.  '  In  the  ex- 
tremities of  large  cylindrical  bones,  holes 


should  be  bored,  about  the  size  of  a  quill, 
to  give  the  water  access  to  their  cavities 
and  a  free  exit  to  medullary  substance.  As 
the  water  evaporates  from  the  vessel,  it 
should  be  so  far  renewed  as  to  keep  the 
bones  under  its  surface,  or  they  will  acquire 
a  disagreeable  blackness,  and  dust  should 
be  excluded  by  keeping  the  vessel  constantly 
covered.  When  the  white  textures  are  de- 
stroyed, the  bones  must  be  scraped  and 
again  laid  in  water  for  a  few  days,  and 
well  washed  and  scrubbed  with  a  coarse 
brush ;  then  immerse  them  in  lime-water, 
or  a  solution  of  pearlash,  made  with  two 
ounces  to  the  gallon  of  water,  and  after  a 
week  they  are  to  be  again  washed  in  clean 
water.  They  are  then  to  be  bleached  on 
the  seashore,  where  they  can  be  daily  washed 
with  sea-water.* 

M.  Bogros  approves  of  the  above  plan  of 
maceration,  but  at  the  conclusion  of  this  he 
directs  them  to  be  boiled  four  hours  in  a 
strong  solution  of  carbonate  of  potass,  or 
in  soap  suds,  adding  hot  water  as  fast  as  it 
evaporates.  They  are  then  to  be  washed 
frequently  in  cold  water,  and  dried  each 
time  quickly,  and  then  moistened  (not 
steeped)  in  weak  muriatic  acid.  The  com- 
mon bleaching  liquor  in  a  diluted  state  will 
whiten  bones,  but  they  should  not  be  im- 
mersed in  it  any  length  of  time. 

When  bleached,  they  may  be  varnished 
with  the  white  of  an  egg.f 

TO   RENDER   SOLID   BONES  FLEXIBLE  AND 

TRANSPARENT. 

One-half  of  the  inferior  jaw  bone,  or  the 
scapula,  are  the  most  suitable  bones  for  the 
above  purpose.  Macerate  either  or  both 
until  they  are  properly  cleansed.  Then  im- 
merse in  a  mixture  consisting  of  water, 
twenty -fiveparts ;  muriatic  acid,  one  part.  If 
the  bone  is  kept  well  covered  Tiuring  a 
period  of  about  seven  months,  it  will  become 
flexible  like  cartilage ;  but  as  the  phosphate 
of  lime  in  the  bone  will  neutralize  some  of 
the  acid,  a  minute  quantity  may  from  time 
to  time  be  added. 

*  Pole  on  "  Cleansing  Bones." 

t  Parsons  on  "Macerated  Preparations." 


86 


ANATOMY   AND    PHYSIOLOGY   OF 


When  the  preparation  becomes  flexible, 
immerse  in  warm  water ;  then  give  it  sev- 
eral washings  in  cold  water  to  remove  the 
acid  ;  dry,  and  immerse  in  a  glass  vessel  of 
oil  of  turpentine  ;  it  will  assume  a  beautiful 
transparency,  exhibiting  the  blood-vessels. 

METHOD  OF  CLEANING  AND  SEPARATING  THE 
BONES  OF  CRANIUM. 

Take  the  head  of  a  young  colt,  remove 
the  skin  and  muscles,  and  wash  out  the 
brain,  previously  breaking  it  down  with  a 
stick  or  probe ;  macerate  and  cleanse  it  as 
before  directed ;  then  fill  the  cranial  cavity 
with  dry  corn  from  the  husk,  immerse  it  in 
water,  and  the  corn  as  it  swells  forces  open 
the  suturuses,  so  that  they  can  be  readily 
separated  by  the  hand.  Wash,  dry,  and 
bleach  the  bones,  and  then  cover  them  with 
colorless  varnish. 

A  BRIEF  EXPOSITION  OF  MR.  SWAN's  NEW 
METHOD  OF  MAKING  DRIED  ANATOMICAL 
PREPARATIONS.* 

The  new  method  has  been  adopted  by 
Usher  Parsons,  M.  D.,  Professor  of  Anat- 
omy and  Physiology,  from  whose  work  the 
following  selections  are  made : 

DIRECTIONS  FOR  MAKING  DRIED  PREPARATIONS. 

The  part  of  a  limb,  chosen  for  injection, 
must  be  as  free  from  fat  as  possible.  A  solu- 
tion of  two  ounces  of  oxy  muriate  of  mercury 
in  half  a  pint  of  rectified  spirits  of  wine,  is 
to  be  injected  into  the  arteries ;  the  next  day 
inject  as  much  white  spirit  varnish,  to  which 
one-fifth  of  white  spirit  varnish  has  been 
added,  and  some  vermilion ;  the  limb  is 
then  to  be  put  into  hot  water,  where  it  is  to 
remain  until  properly  heated,  when  the  coarse 
injection  is  to  be  thrown  into  the  arteries 
and  veins,  if  required,  bearing  in  mind  the 
course  of  J:he  circulation ;  the  valves  of  the 
veins  can  be  broken  down  by  a  whalebone 
probe,  if  necessary.  If  the  veins  are  to  be 
injected,  it  is  better  to  wash  the  blood  out  of 
them  with  water  before  the  solution  of  oxy- 

*  Professor  Chaussicr  claims  to  be  the  ori^^inal  dis- 
coverer of  this  method. 


muriate  of  mercury  is  thrown  into  the  arte- 
ries. 

After  the  limb  has  been  injected,  it  is  to 
be  dissected.  Every  time  it  is  left,  and 
sometimes  during  dissection,  it  is  advisable 
to  cover  those  parts  which  have  been  ex- 
posed, with  a  damp  cloth.  There  are  great 
advantages  to  be  derived  from  previously 
injecting  the  limb  in  oxy  muriate  of  mercury, 
for  a  limb  thus  injected  undergoes  very  little 
change  in  many  days,  and,  when  the  dissec- 
tion is  recommenced,  the  parts  will  be  found 
in  the  same  state  in  which  they  were  left, 
and  destitute  of  any  offensive  odor. 

The  oxymuriate  of  mercury  is  the  best 
agent  for  arresting  the  putrefactive  process. 

After  the  dissection  is  finished,  the  limb, 
or  part,  must  be  immersed  in  a  solution  of 
oxymuriate  of  mercury  for  a  fortnight  or 
more. 

The  solution  of  oxymuriate  of  mercury 
must  be  contained  in  a  wooden  vessel,  as 
metallic  vessels  do  not  answer. 

The  limb,  or  part,  having  been  in  the 
solution  during  the  above  period,  it  should 
be  taken  out,  diied,  varnished,  and,  if  neces- 
sary, painted. 

SOLUTION     OF     HARDENING     THE     BRAIN     AND 
OTHER    TISSUES. 

Take  of  oxymuriate  of  mercury,  one 
ounce ;  muriate  of  ammonia,  thirty-five 
gi-ains ;  pyroligneous  acid,  one  pint.  Rub 
the  oxymuiiate  of  mercury  and  muriate  of 
ammonia  together  in  a  mortar,  then  add 
half  a  pint  pyrloigneous  acid. 

OXYMURIATE     OF     MERCURY     IS     A     VALUABLE 
ANTISEPTIC. 

Dr.  Parsons  relates,  that,  when  a  piece  of 
flesh  had  been  immersed  in  a  solution  of 
oxymuriate  of  mercury  until  it  was  com- 
pletely changed,  and  afterwards  put  into  a 
large  vessel  containing  water  for  some  days, 
though  the  greater  part  of  the  oxymuriate 
of  mercury  was  thus  washed  away,  it  did 
not  even  then  appear  in  the  least  degree 
putrid.  I  procured  half  of  the  head  and 
neck  of   a  large  horse,  which  I  first  injected 


THE   HORSE. 


87 


with  the  solution  of  oxymuriate  of  mercury, 
but  as  the  putrefactive  process  was  not  thus 
sufficiently  stopped,  without  dissecting  off 
the  skin  I  immersed  it  in  the  solution  of 
oxymuriate  of  mercury  for  several  days ; 
and,  as  no  marks  of  putrefaction  remained 
(the  offensive  smell  being  entirely  removed), 
I  then  put  it  into  a  vessel  containing  a 
large  quantity  of  water  for  two  or  three 
days  more,  by  which  means  nearly  all  the 
solution  was  removed  from  it.  I  was  thus 
able  to  proceed  with  the  dissection  during 
the  hot  weather,  without  being  in  the  least 
incommoded  either  by  the  smell  or  soreness 
of  the  hands,  and  without  finding  the  instru- 
ments acted  upon  in  any  degree,  that  ren- 
dered the  process  at  all  objectionable.  By 
putting  a  wet  cloth  over  it  when  I  left  it,  I 
was  further  enabled  to  make  a  very  minute 
dissection  of  the  nerves,  which  I  could  not 
otherwise  have  done,'  without  the  use  of  a 
large  quantity  of  spirits  of  wine,  and  then 
not  with  half  the  convenience  and  pleasure 
I  have  thus  experienced. 

ON   VARNISHES   AND   PAINTS. 

The  following  are  the  recipes  for  the 
manufacture  of  paints  and  varnishes: 

WHITE    VARNISH. 

Canada  balsam,  spirits  of  tm'pentine,  of 
each  three  ounces ;  mastic  varnish,  two 
ounces.  Put  them  into  a  bottle  and  shake 
them  together  until  they  are  properly 
mixed. 


MASTIC    VARNISH. 

This  may  be  made  by  putting  four 
ounces  of  powdered  mastic  into  one  pint 
of  spirit  of  turpentine,  to  be  kept  in  a 
stoppered  bottle.  It  should  be  shaken  every 
day  until  the  greater  part  of  the  mastic 
is  dissolved. 

TURPENTINE    VARNISH. 

Turpentine  varnish  is  made  by  melting 
Venice  turpentine  over  a  slow  fire,  and  add- 
ing to  it  as  much  spirits  of  turpentine  as 
will  reduce  it  to  the  consistence  of  syrup. 

WHITE    PAINT. 

Three  ounces  of  the  best  white  paint, 
and  one  ounce  of  spirit  of  turpentine,  are 
to  be  put  into  a  bottle  and  shaken  together. 
When  it  is  used  with  the  varnish,  a  bottle 
of  each  should  be  mixed  together. 

PAINT    FOR    THE    MUSCLES. 

This  is  made  by  grinding  on  a  slab  a 
small  quantity  of  "  /aA;e,"  with  white  var- 
nish, to  which  one-fourth  part  of  turpen- 
tine varnish  has  been  added. 

Dr.  Parsons  directs  that  varnish  should 
be  laid  on  with  a  fine  camels'-hair  pencil 
brush,  as  large  as  occasion  may  require. 
Hollow  preparations  should  have  the  var- 
nish poured  into  them,  and,  after  turning 
them  about  in  aU  directions,  it  is  to  be 
drained  out  as  clear  as  possible. 


DIGESTIVE    SYSTEM. 


OF   THE    MOUTH. 

It  may  be  observed  here  (as  preparatory 
to  the  description  of  this  part),  that,  in 
quadrupeds  in  general,  the  facial  angle  is 
one  of  very  considerable  obliquity,  in  con- 
sequence of  the  prolongation  of  that  part 
of  the  head  which  corresponds  to  the  face 
in  the  human  subject;  and  this  develop- 
ment of  feature  is  in  none  more  strildna: 
than  in  the  horse  and  dog.  Consequently,  in 
these  animals,  the  nose  and  mouth  are 
cavities  of  large  dimensions.  And  in  the 
horse,  the  mouth  appears  to  have  been  thus 
prolonged,  not  only  to  enable  him  to  col- 
lect his  food  with  more  facility,  but  also 
that  he  might  subject  greater  parcels  of  it 
at  a  time  to  the  action  of  the  grinding 
teeth,  whereby  the  processes  of  mastication 
and  deglutition  are  greatly  accelerated. 

"  Conformation.  —  The  mouth  is  con- 
structed in  part  of  bone,  and  in  part  of 
soft  materials.  The  superior  and  anterior 
maxillary  and  the  palate  bones  form  the 
roof;  the  inferior  maxilla,  the  lower  part; 
the  incisive  teeth,  the  front  ;  and  the 
molar  teeth,  the  sides.  The  lips,  cheeks, 
soft  palate,  gums,  and  buccal  membrane, 
constitute  its  soft  parts.  The  tongue  occu- 
pies its  cavity,  and  the  salivary  glands  are 
appendages  to  it. 

"lips. 

"  General  Conformation.  —  The  lips,  two 
in  number,  superior  and  inferior^  are  at- 
tached to  the  alveolar  projections  of  the  su- 
perior and  inferior  maxilla3,  by  the  muscles 
that  move  them ;  by  the  cellular  tissue  en- 
tering into  their  composition ;  and  by  the 
membrane  that  lines  them.  Their  borders 
surround    and    bound    the    orifice    of    the 


mouth,  and  are  united  together  on  either 
side ;  which  points  of  union  are  denomi- 
nated their  commissures,  or  the  angles  or 
corners  of  tlie  mouth.  Exteriorly,  the  lips 
are  creased  down  the  middle  by  perpen- 
dicular lines  of  division  ;  exhibit  little 
papillary  eminences  upon  their  sm-face  ; 
and  present  a  softer  and  shorter  coating  of 
hair  than  what  is  found  in  ordinary  places, 
out  of  which  project  several  long  sti*aggUng 
horse-hairs  or  ivhiskers.  The  inferior  lip 
is  altogether  smaller,  and  is  thinner  in  sub- 
stance, than  the  superior ;  and  is  distin- 
guished by  a  remarkable  prominence  about 
its  centre,  from  which  gi'ows  a  tuft  of  long 
coarse  hairs,  vulgarly  designated  as  the 
beard. 

"  Structure.  —  The  lips  are  both  muscu- 
lar and  glandular  in  their  composition. 
Several  small  muscles,*  arising  from  the 
maxillary  bones,  are  inserted  into  them,  and 
endow  them  with  great  self-mobility :  one 
alone,  consisting  of  circular  fibres,  is  inter- 
woven in  their  substance  without  having 
any  other  connection ;  this  is  denominated 
the  orbicularis  oris,  or  sphincter  labiorum, 
from  its  use,  which  is  that  of  closing  the 
mouth.  This  muscle  is  an  antagonist  to 
all  the  others ;  they  raise  or  depress  the 
lips,  or  draw  them  to  one  side ;  but  this 
contracts  them,  and  occasionally  projects 
them  in  such  a  manner  that  the  horse  can 
exert  with  them  a  prehensile  power,  which 
is  most  remarkably  evinced  at  the  time  that 
he  is  picking  up  grain  from  a  plain  sm'face ; 
indeed,  the  act  of  nibbling  our  hands  with 
his  lips  demonstrates  this  faculty,  and  also 
the  force  with  which  he  can  employ  it.  The 
lips  are  lined  by  the  same  membrane  that 
lines  other  parts  of  the  cavity  of  the  mouth. 

*  PercivaH's  Hyppopathology. 

(88) 


THE   HOESE. 


89 


Beneath  it  are  seated  numerous  mucous 
follicles,  that  elevate  it  everywhere  into  lit- 
tle papillcB,  which  are  perforated  by  the 
mouths  of  these  follicular  glands,  as  may 
be  readily  seen  with  the  naked  eye  by  evert- 
ing either  the  superior  or  the  inferior  lip. 
The  skin  covering  the  lips  is  extremely 
thin,  and  possesses  considerable  vascularity 
and  sensibility.  To  the  tenuity  of  it,  and 
to  the  shortness  and  scantiness  of  their 
pilous  covering,  is  to  be  ascribed  the  su- 
perior sensitive  faculty  of  these  parts. 

"  CHEEKS. 

"  The  cheeks  are  constituted  substantially 
of  the  masseter  and  buccinator  muscles, 
covered  by  the  skin  upon  the  outside,  and 
the  buccal  membrane  upon  the  inside. 
Their  internal  or  membranous  surface  is 
studded  with  scattered  mucous  follicles, 
whose  excretory  orifices  may  be  seen  by 
everting  the  part. 

"  GUMS. 

"  The  gums  consist  of  dense,  compact, 
prominent,  polished  masses,  of  the  nature 
of  periosteum,  adhering  so  closely  and 
tenaciously  to  the  teeth  and  the  sides  of 
then*  sockets,  that  it  renders  the  one  insep- 
arable from  the  other,  but  by  extraordinary 
mechanical  force.  Like  other  parts  of  the 
cavity  of  the  mouth,  they  receive  a  cover- 
ing from  the  buccal  membrane. 

"  PALATE. 

"  Two  distinct  parts  are  included  under 
this  head ;  the  hard  and  the  soft  palate. 
The  hard  palate  is  constituted  of  the  pala- 
tine processes  of  the  superior  and  anterior 
maxillary  bones  ;  and  of  a  firm,  dense, 
periosteum-like  substance,  the  vaulted,  in- 
ward part  of  which  is  elevated  into  several 
semicircular  ridges,  vulgarly  called  the  bajs. 
The  fibres  of  this  substance,  which  pos- 
sess great  tenacity,  are  inserted  into  the 
pores  of  the  bone  in  every  part,  but  are 
most  numerous  and  dense  along  the  pala- 
tine suture :  the  interstices  are  filled  up  by 
a   dense  cellular  tissue,  through  the  sub- 

12 


stance  of  which  are  dispersed  the  ramifica- 
tions of  the  palatine  vessels  and  nerves. 

"  The  soft  palate,  sometimes  called  the 
velum  palaii,  is  attached  to  the  superior  or 
crescentic  border  of  the  hard  palate,  the 
border  formed  by  the  palatine  bones ;  from 
wliich  the  velum  extends  backward  and 
downward  as  far  as  the  larynx,  and  there 
terminates  over  the  epiglottis,  in  close  ap- 
position with  that  part,  in  a  loose  semi- 
circular edge.  In  consequence  of  the 
velum  palati  being  long  enough  to  meet  the 
epiglottis,  the  cavity  of  the  mouth  has  no 
communication  with  that  of  the  nose  — 
these  two  parts  forming  a  perfect  septum 
between  them ;  hence  it  is  that  a  horse 
cannot  respire  and  vomit  by  the  mouth  lilic 
a  human  being,  in  whom  the  velum  is  so 
short  that  there  is  an  open  space  left  be- 
tween it  and  the  epiglottis,  through  which 
air  or  aliment  can  pass  either  upward  or 
downward.  The  soft  palate  is  composed 
of  extensions  of  membrane  from  the  nose 
and  mouth,  between  which  is  interposed  a 
pale,  thin  layer  of  muscular  fibres.     ' 

"  The  velum  performs  the  office  of  a 
valve :  it  prevents  the  food,  in  the  act  of 
swallowing,  from  passing  into  the  nose,  and 
it  conducts  the  air  from  the  windpipe  into 
that  cavity,  without  permitting  any  to 
escape  into  the  mouth. 

"  OF    THE    TONGUE. 

"  The  tongue,  the  principal  organ  con- 
cerned in  taste  and  deglutition,  is  lodged  in 
the  mouth ;  filling  the  interspace  between 
the  branches  of  the  inferior  maxilla. 

'-'■  Duplicitij. —  Like  the  other  organs  of 
sense,  it  is  double ;  being  composed  of  two 
parts,  whose  union  is  marked  by  a  longitu- 
dinal crease  along  its  middle,  the  divisions 
having  no  vascular  nor  nervous  connection 
nor  in  fact  any  intercommunication  what- 
ever ;  so  that  an  animal  has  to  all  intents 
and  purposes  tiuo  tongues,  and  apparently 
for  the  same  reason  that  he  has  two  eyes, 
two  ears,  and  two  nostrils.  Anatomy,  as 
far  as  we  can  carry  our  researches,  demon- 
strates  this ;   perhaps  we   have   no   better 


90 


ANATOMY   AND    PHYSIOLOGY  OP 


proof  of  it,  however,  than  what  happens  in 
hemiplegia,  a  disease  in  which  only  one 
half  of  the  body  is  paralytic :  under  these 
circumstances,  in  the  human  subject,  the 
patient  can  only  see  with  one  eye,  use  one 
arm,  and  taste  with  but  one  (and  that  the 
correspondent)  side  of  the  tongue. 

"  Division.  —  The  tongue,  in  description, 
is  commonly  divided  into  root,  body,  and 
apex  :  by  the  attachments  of  the  two  former 
it  is  held  in  its  situation  ;  the  latter  is  loose 
and  unconnected. 

"  Attachment.  —  At  its  root,  it  is  deeply 
and  firmly  inserted  by  several  muscles  which 
arise  chiefly  from  the  os  hyoides  and  the 
inferior  maxilla :  it  is  also  connected  with 
the  pharynx,  and  with  the  soft  palate. 
From  the  sides  of  the  lower  jaw,  separate 
layers  of  the  membrane  of  the  mouth  are 
reflected  upon  its  body,  forming  by  their 
junction  a  sort  of  bridle,- which  is  thence 
extended  to  the  symphysis :  to  this  part, 
which  serves  to  restrain  the  organ  in  its 
motions,  the  name  of  frcenum  linguce  has 
been  given. 

"  Papilla.  —  The  dorsum  or  anterior  sur- 
face of  this  organ  has  a  peculiar  covering, 
which,  though  it  appears  to  be  continued 
from  the  buccal  membrane,  is  a  different 
structure  altogether,  and  serves  quite  a 
different  purpose.  The  surface  of  it  is 
roughened,  possessing  a  villous  texture, 
everywhere  studded  with  numerous  little 
conical  eminences,  called  papilla;,  which  are 
supposed  to  be  formed  out  of  the  extremi- 
ties of  the  nerves,  and  to  be  the  especial 
seat  of  the  sense  of  taste.  These  papillsB 
vary  in  size  and  figure,  and  are  more  abun- 
dant and  larger  upon  the  base  and  along 
the  sides  of  the  organ.  Interspersed  with 
them  are  a  number  of  mucous  follicles, 
whose  apertures  may  be  seen  with  the  naked 
eye,  through  which  a  mucus  is  discharged 
upon  the  papillary  surface,  keeping  it  con- 
tinually moist,  and  rendering  its  perception 
of  taste  more  acute. 

"  Structure.  —  The  tongue  is  said  to  pos- 
sess a  covering  of  common  integument ; 
and  certainly  its  strong,  compact  tunic  has 
all  the  appearances  of  skin,  and  presents 


the  common  tests  of  it :  the  external  layer 
is  laminated,  is  bloodless,  is  insensible  ;  the 
internal  or  substantial  part  is  tough,  fibrous, 
vascular,  and  sensitive,  in  fact,  is  like  cutis ; 
and  the  intermediate  or  connecting  material 
is  delicate,  soft,  ond  reticular,  and  forms  a 
bed  for  the  lodgment  of  the  papillsB.  The 
substance  of  the  tongue  itself  consists  of 
an  inter-union,  or  rather  an  incorporation, 
of  its  muscles,  the  fibres  of  which  intersect 
one  another,  and  take  a  variety  of  direc- 
tions ;  but  intermixed  with  them  is  a  fine 
adipose  tissue,  to  which  is  owing  the  flabby 
softness  of  the  organ,  and  the  peculiar 
aspect  it  exhibits  when  cut  into. 

"  Use.  —  Though  the  tongue  is  empha- 
tically denominated,  from  its  essential  char- 
acter, the  organ  of  taste,  it  is  not  the  only 
part  that  possesses  this  faculty ;  for  the  palate, 
the  pharynx,  and  the  oesophagus,  it  is  be- 
lieved, participate  in  it.  The  tongue,  in 
addition  to  possessing  this  faculty,  disposes 
of  the  food  during  nianducation,  and,  when 
sufficiently  masticated,  coUects  and  thrusts 
it,  portion  after  portion,  into  the  pharynx ; 
and  furthermore,  at  the  time  the  animal  is 
drinking,  it  is  not  only  employed  as  an  in- 
strument of  suction,  but  also  as  a  canal 
along  which  the  fluid  ascends  into  the 
pharynx. 

"  Organization.  —  Every  part  of  this  or- 
gan is  plentifully  supplied  with  blood.  Its 
arteries  are  the  lingual,  branches  of  large 
size  from  the  external  carotids.  The  blood- 
vessels of  either  side  are  generally  found 
free  from  anastomosis  with  one  another ;  if 
either  of  the  arterial  trunks  is  filled  with 
injection,  it  rarely  happens  that  the  opposite 
half  of  the  organ  receives  any  coloring  from 
it.  Its  nerves  are  the  ninth  pair,  which  run 
to  the  muscles,  and  a  considerable  branch 
from  the  fifth  pair,  in  whose  extreme  rami- 
fications, which  are  distributed  to  the  papillae, 
the  perception  of  taste  is  supposed  to  be 
inherent. 

"OF    THE   SALIVARY  GLANDS. 

"  Number  and  Names.  —  The  salivary 
glands,  properly  so  called,  are  six  in  number, 
three   upon    each   side   of    the   head ;    the 


EXPLANATION   OF   FIGURE  X. 


OSSEOUS   STRUCTURE. 

(SEE  PKECEDINO  PLATE.) 

MUSCULAR  STRUCTURE. 

LATERAL  VIEW. 


a". 

Trapezius. 

#^ 

Ligamentmn  colli. 

6". 

Rhomboideus  longus. 

c". 

Scalenus. 

/" 

'.  Antea  spinatus. 

9"- 

,  Postea  spiiiatus. 

7i". 

Teres  major. 

t". 

Latissimus  dorsi. 

r. 

m".  «".  Triceps  extensor  brachii. 

s. 

Splenius. 

K. 

Masseter. 

a. 

Orbicularis  palpebrarum. 

c. 

Dilator  naris  lateralis. 

€. 

Orbicularis  oris. 

/• 

Nasalis  longus. 

9- 

Levator  labii  superiorus. 

h. 

Buccinator. 

i. 

Zygomaticus. 

J. 

Depressor  labii  inferiorus. 

m. 

Attolentes. 

n. 

Retrahentes  aurem. 

0. 

Abducens  vel  deprimens  aurem. 

q.'> 

r.  Tendon  of  the  splenius  and  complexus 

major. 

t. 

Obliquus  capitis  inferiorus. 

u. 

Levator  humeri. 

X. 

Subscapulo  hyoideus. 

VEINS. 

1. 

Temporal  vein. 

2. 

Facial          " 

3. 

10. 

Branch  of  the  jugular. 
Parotid  gland 

THE   HORSE. 


91 


parotid,  the  submaxillary,  and  the  sub- 
lingual. 

"  The  parotid,  the  largest  of  these  glands, 
so  called  from  being  placed  near  the  ear, 
lies  within  a  hollow  space  at  the  upper  and 
back  part  of  the  head,  bounded  by  the 
branch  of  the  lower  jaw  before,  and  the 
petrous  portion  of  the  temporal  bone  behind : 
it  extends  as  high  up  as  the  root  of  the  ear, 
and  as  low  down  as  the  angle  of  the  jaw, 
by  which  latter  a  small  portion  of  it  is  con- 
cealed. This  gland,  like  the  others  of  the 
same  class,  is  enveloped  in  a  case  of  dense 
cellular  membrane,  and  is  constituted,  in 
structure,  of  many  little  lobes  or  lobuli,  con- 
nected together  by  processes  transmitted 
into  the  interior  from  this  cellular  covering. 
Every  lobulus  is  composed  of  a  distinct  set 
of  secretory  vessels,  from  which  numerous 
tubuli  arise,  conjoin,  and  at  length  form  one 
main  branch ;  these  branches,  which  corre- 
spond in  number  to  the  lobuli,  unite  and 
re-unite  until  they  end  in  one  common  ex- 
cretory duct.  The  duct  emerges  from  the 
inferior  part  of  the  gland,  runs  along  the 
inner  part  of  the  angle  of  the  jaw,  and 
crosses  over  the  posterior  edge  of  the  bone 
immediately  above  or  behind  the  submaxil- 
lary artery  and  vein :  in  the  remainder  of 
its  course  it  corresponds  to  the  border  of 
the  masseter,  and,  about  opposite  to  the 
second  anterior  molar  tooth,  pierces  ob- 
liquely the  buccinator,  and  terminates  by  a 
tubercular  eminence  upon  the  internal  sur- 
face of  the  buccal  membrane.* 

"  The  submaxillary  gland,  of  smaller 
volume  than  the  parotid,  lies  in  the  space 
between  the  angles  of  the  jaw,  to  which,  and 
to  the  muscles  thereabouts,  it  is  loosely 
attached  by  cellular  membrane :  a  portion 
of  it   is   also   generally   found   proceeding 

*  To  expose  this  duct,  at  or  near  its  issue  from  the 
gland,  an  incision  should  be  earned  along  the  posterior 
border  of  the  branch  of  the  lower  jaw  :  first,  dividing  the 
skin ;  secondly,  the  panniculus ;  thirdly,  the  cellular  tissue 
immediately  covering  the  duct,  which  is  readily  dis- 
tinguished by  its  glistening  pellucid  aspect.  By  extending 
the  incision  around  the  angle  of  the  jaw,  directing  it 
towards  the  inner  edge  of  the  bone,  the  duct  will  be  found 
making  its  first  turn  :  here,  however,  it  is  lodged  in  a 
hollow,  deeply  buried  in  cellular  tissue. 


backward  as  far  as  the  trachea.  Its  struc- 
ture is  similar  to  that  of  the  parotid  gland. 
The  submaxillary  duct  issues  near  the 
centre  of  the  gland,  creeps  along  the  under 
and  inner  border  of  the  tongue,  close  to  the 
lower  edge  of  the  sublingual  gland,  and 
terminates  by  a  little  mammiform  elongation 
of  membrane,  vulgarly  called  the  barb  (bar- 
billon)  or  pap,  upon  the  frsenum  linguae, 
about  half  an  inch  above  its  attachment  to 
the  symphysis.  Among  the  other  ridiculous 
and  miscliievous  practices  of  farriers  is  that 
of  snipping  off  these  processes.  They 
were  seemingly  designed  as  valves,  to  pre- 
vent the  insinuation  of  alimentary  matters 
into  the  ducts.  The  coats  of  this  vessel  are 
extremely  thin  and  translucent. 

"  The  sublingual  gland  is  still  smaller  in 
volume  than  the  submaxillary,  though,  al- 
together, one  much  resembles  the  other  in 
figure.  It  lies  along  the  under  part  of  the 
tongue,  covered  by  the  buccal  membrane, 
where,  from  the  lobular  unevenness  it  gives 
to  the  surface,  its  situation  is  well  marked. 
Its  ducts  penetrate  the  membrane  by  the 
side  of  the  freenum  linguEe. 

"  The  use  of  the  salivary  glands  is  to 
secrete  a  saline  limpid  fluid,  called  saliva; 
which  is  conveyed  and  poured  by  their 
ducts  into  the  mouth  during  manducation  : 
here  it  is  mixed  with  the  food,  mollifying  it, 
and  rendering  it  more  easy  of  digestion,  and 
at  the  same  time  facilitating  the  passage  of 
the  alimentary  bolus  into  the  stomach. 

"  OF    THE    PHARYNX. 

"  The  pharynx  is  a  funnel-shaped  sac, 
lodged  in  the  throat  for  the  reception  of  the 
food. 

"  Situation.  —  The  pharynx  is  contiguous 
to  the  guttural  pouches,  superiorly;  the 
larynx,  inferiorly  ;  and  the  anterior  portions 
of  the  parotid  glands  and  branches  of  the 
jaw,  laterally.  Posteriorly,  it  is  continuous 
in  substance  with  the  esophagus  ;  anteriorly, 
it  presents  an  opening  to  the  mouth. 

"  Attachment.  —  In  front,  to  the  os  hyoides 
and  palate  bones  ;  below,  to  the  larynx ; 
behind,  it  grows  narrow  and  ends  in  the 
esophagus. 


92 


ANATOMY   AND   PHYSIOLOGY   OP 


"  Stmcture.  —  The  pharynx  is  in  part 
muscular,  and  in  part  membranous.  Of 
the  muscles  belonging  to  it  Ihe  constric- 
tors are  those  that  more  immediately  enter 
into  its  composition.  They  are  so  dis- 
posed as  to  give  the  membrane  forming 
the  sac  a  complete  fleshy  covering,  which 
is  rendered  the  more  uniform  by  their 
proximate  fibres  being  indistinguishably 
blended:  thus  the  muscles  form  the  most 
substantial  part  of  the  pharynx.  The 
lining  membrane,  which  is  of  the  mu- 
cous class,  is  soft  and  thick  in  substance, 
and  palely  tinged  with  red  in  color,  and  is 
papillary  and  in  places  rugose  upon  its  sur- 
face ;  being  perforated  by  the  ducts  of 
numerous  follicles  which  discharge  a  mucus 
that  preserves  glibness  and  moisture  to  its 
interior.  The  membrane  itself  is  (where  it 
meets  them)  continuous  both  with  the  buc- 
cal membrane  and  that  which  lines  the 
esophagus. 

"  Although  the  pharynx  is  designed  for 
the  reception  of  the  food,  it  does  not  open 
directly  into  the  mouth ;  the  two  cavities 
are  separated  from  each  other  by  the  soft 
palate  and  epiglottis.  Except  in  the  act  of 
sw^allowing  and  coughing,  they  have  no 
communication :  in  the  former  case,  the 
velum  is  pressed  upward  by  the  food 
against  the  posterior  openings  of  the  nose ; 
in  the  latter,  the  larynx  is  depressed  by  a 
convulsive  action  of  the  muscles  in  the 
vicinity.  Into  the  cavity  above  the  velum 
there  are  four  openings  —  two  of  the  cham- 
bers of  the  nose,  one  of  the  larynx,  and  one 
of  the  esophagus :  the  eustachian  tubes  do 
not  open  into  the  pharynx;  they  end  in 
two  large  membranous  pouches  at  the 
upper  part  of  the  fauces.  The  opening 
leading  into  the  esophagus  is  constantly 
closed,  except  when  alimentary  matters  are 
passing  to  or  from  the  stomach ;  so  that  air 
received  into  the  pharynx  through  the  nose 
can  pass  nowhere  else  but  into  the  wind- 
pipe ;  but  if  food  be  returned  from  the 
stomach,  it  will  be  regurgitated  into  the 
nose  ;  at  least,  only  that  portion  of  it 
which  enters  the  pharynx  at  the  moment 
that  the  larynx  is  depressed   in  the  act  of 


vomiting,  can  be  thrown  into  the  mouth, 
in  the  same  way  that  air  is  in  the  act  of 


coughing. 


"  OF    THE    ESOPHAGUS. 


"  The  esophagus,  or  gullet,  is  the  tube 
through  which  the  food  is  conducted  from 
the  pharynx  into  the  stomach. 

"  Course. —  It  has  its  beginning  from  the 
pharynx,  and  is  there  placed  at  the  upper 
and  back  part  of  the  larynx,  taking  the 
first  part  of  its  course  above  and  behind  the 
trachea,  between  that  tube  and  the  cervical 
vertebra?.  Having  proceeded  a  short  way 
down,  it  inclines  to  the  left,  and  soon  after 
makes  its  appearance  altogether  on  the  left 
side  of  the  trachea,  and  continues  so  placed 
during  the  remainder  of  its  passage  down 
the  neck :  this  explains  why  we  look  for  the 
bolus  during  the  act  of  swallowing  on  the 
left,  and  not  on  the  right  side  of  the  ani- 
mal. In  company  vvdth  the  trachea,  the 
esophagus  enters  the  thorax  between  the 
first  tw^o  ribs,  at  which  place,  running  above 
that  tube,  it  quits  its  companion  for  the 
superior  mediastinum,  which  ca\dty  it 
traverses  below  and  a  little  to  the  right  of 
the  posterior  aorta.  Immediately  beneath 
the  decussation  of  the  crura,  the  esophagus 
pierces  the  substance  of  the  diaphragm, 
and  enters  the  stomach,  at  a  right  angle, 
about  the  centre  of  its  upper  and  anterior 
part. 

"  Structure.  —  The  esophagus  presents, 
externally,  a  strong,  red,  muscular  coat ;  in- 
ternally, one  remarkable  for  its  whiteness, 
which  in  its  nature  is  cuticular.  The  mus- 
cular coat  is  composed  of  two  orders  of 
fibres  —  a  longitudinal,  forming  an  out- 
ward layer  ;  and  a  circular,  an  inward 
layer  :  the  former  will  shorten  the  tube,  and 
perhaps  dilate  it  for  the  reception  of  food  ; 
the  latter,  by  successive  contractions  of  the 
canal,  wiU  transmit  the  food  into  the 
stomach.  The  second,  or  internal  coat,  is 
called  the  cuticular,  from  its  analogy  to  the 
cuticle  of  the  skin.  Although  it  is  contin- 
uous with  the  membrane  of  the  pharnyx, 
it  is  of  a  totally  different  composition  :  it  is 
thinner,  but  it  is  much  more  compact  and 


THE   HORSE. 


93 


stronger  in  its  texture,  and,  I  believe,  is 
both  insensible  and  inorganic.  It  adheres 
to  the  muscular  covering  by  a  fine  cellular 
tissue,  the  extensibility  of  which  gives  full 
play  to  the  latter  ;  and  admits,  during  the 
empty  or  collapsed  state  of  the  tube,  of  the 
former  being  thrown  into  many  longitudinal 
plicce  or  folds  ;  as  is  demonstrated  by  mak- 
ing a  transverse  section  of  the  tube :  such 
appearances  result  from  the  contraction  of 
the  one  coat,  and  the  want  of  proportion- 
ate elasticity  in  the  other.  Between  the 
two  tunics,  imbedded  amongst  the  connect- 
ing cellular  tissue,  are  numerous  follicular 
glands,  whose  office  is  to  pour  forth  a  mu- 
cous secretion  upon  the  internal  surface  of 
the  lining  membrane,  to  render  the  passage 
of  food  along  it  glib  and  free  from  any 
friction. 

"  NASAL    FOSSiE.* 

"  The  nasal  fossae  are  the  two  chambers 
or  lateral  cavities,  whose  external  openings 
are  the  nostrils.  Their  walls  or  external 
parietes  are  almost  entirely  osseous ;  and  to 
the  OSSEOUS  SYSTEM  (page  45)  the  reader 
must  turn  for  a  description  of  the  manner 
in  which  the  fossae  are  formed,  and  of  the 
bones  entering  into  their  formation.  But, 
in  addition  to  bone,  they  are  cartilaginous 
in  their  constitution. 

"  The  cartilages  of  the  nose  are  five  in 
number: — of  which  one  (the  septum  nasi) 
is  situated  internally ;  the  other  four  (enter- 
ing into  the  composition  of  the  nostrils)  ex- 
ternally. 

"  The  septum  nasi  is  the  vertical  carti- 
laginous partition  interposed  between  the 
nasal  fossae.  It  exhibits  four  borders.  The 
inferior  one  is  received  into  the  groove  of 
the  vomer ;  while  the  superior  presents  a 
lengthened  channel  between  two  elevated 
edges,  into  which  is  admitted  the  internal 
crest  formed  by  the  union  of  the  nasal 
bones.  Its  posterior  border  is  affixed  to  the 
ethmoidal  plate  :  its  anterior  serves  to  sus- 
tain the  cartilages  forming  the  nostrils. 
Both  its  sides  are  completely  covered  by  the 
Schneiderian  membrane. 

*  Hippopathology. 


"  Nostrils.  —  Four  in  number  :  two  on 
each  side,  distinguished  by  the  epithets  true 
and  false. 

"  The  true  nostrils  are  the  large,  ovoid, 
and  ever-open  orifices  so  conspicuous  ex- 
ternally. They  have  for  the  base  of  their 
structure  four  pieces  of  fibro-cartilage, 
which  are  involved  in  doubfings  of  the 
common  integument.  Each  nostril  is  formed 
of  two  flexible  alee  or  wings  :  a  superior  or 
internal  one,  and  an  inferior  or  external. 
The  former  is  supported  by  a  broad  circular 
cartilaginous  plate  ;  the  latter  is  crescentic 
in  shape,  and  forms  a  flexm*e  outward, 
within  which  is  perceptible  the  orifice  of 
the  lachrymal  duct.  They  are  attached  to, 
and  supported  by,  the  nasal  peak  and  sep- 
tum nasi. 

"  The  false  nostrils  are  t^vo  fittle  pouches 
or  cavities  (having  the  semblance  of  culs- 
de-sacs),  situated  internaUy,  above  the  true 
nostrils,  into  which  an  external  opening  is 
found  within  the  commissure  formed  by  the 
union  of  the  two  alse.  They  are  formed 
out  of  dupficatures  of  the  skin,  which  is 
here  tliinner,  and  finer,  and  softer  in  its 
texture  ;  and,  except  at  their  entrance,  are 
without  hair  upon  their  surfaces.  Their 
use  is  not  known. 

"  Schneiderian  membrane.  —  The  cavity 
of  the  nose  is  not  only  divided  into  the  two 
nasal  fossae,  but  each  fossa  is  subdivided 
into  the  three  meatus  (for  a  description  of 
which,  vide  page  45).  Every  part  of  these 
cavities  and  passages  is  covered  by  the 
Schneiderian  or  pituitary  memh'ane.  This 
is  a  membrane  of  the  mucous  class,  dis- 
tinguished for  its  thickness  of  substance, 
for  its  vascularity,  and  for  its  olfactory  pa- 
pillae. It  has  two  surfaces:  an  exposed 
or  secreting  one  and  an  unexposed  or  ad- 
herent one.  The  secreting  surface  is 
smooth,  and  is  rendered  gfib  and  shiny  by 
the  varnish  it  derives  from  the  mucous 
secretion  emitted  by  the  numerous  small 
rounded  pores  everywhere  visible  in  the 
membrane,  but  more  particularly  upon  the 
lower  part  of  the  septum,  and  upon  the 
inferior  turbinated  bone.  This  surface 
exhibits  a  pale  pink  blush,  the  effect  of  the 


94 


ANATOMY   AND   rHYSIOLOGY   OF 


bloodvessels  spread  over  it,  which  are  here 
so  superficial  as  to  owe  their  principal  de- 
fence to  the  mucous  exudation :  hence  it 
is  that  the  complexion  of  the  membrane 
(varying  with  the  inilucnce  of  the  atmos- 
phere and  other  agents)  is  extremely  fugitive 
and  uncertain.  The  adherent  surface  of 
the  membrane  contracts  a  close  and  firm 
adherence  to  the  parts  it  covers,  through 
the  insinuation  of  its  fibres  into  them  :  in- 
deed, to  the  bone  it  appears  to  supply  the 
place  of  periosteum ;  to  the  cartilage,  of 
perichondrium.  The  substance  of  the 
membrane  exhibits  a  fibrous  structure,  in- 
terwoven with  cellular  tissue ;  and  upon 
that — as  a  substratum  —  is  spread  a  glan- 
dular and  vascular  apparatus,  from  which 
issues  the  mucous  secretion ;  together  with 
numerous  papillce,  of  small  size,  constituted 
of  the  terminations  of  those  nerves  from 
which  the  membrane  derives  ordinary  sen- 
sation, as  well  as  those  that  endow  it  with 
the  peculiar  sense  of  smelling.  The 
Schneiderian  membrane,  inferiorly,  within 
the  nostrils,  is  continuous  with  the  duplica- 
tures  of  skin  lining  those  parts ;  superiorly 
with  the  membrane  lining  the  pharynx ;  be- 
sides which,  it  is  continued  into  the  several 
sinuses  of  the  head,  through  the  openings 
leading  from  them  into  the  nose,  and  like- 
wise gives  them  a  complete  covering  :  it  is 
to  be  observed,  however,  that  in  the  sinuses 
the  membrane  is  thinner,  and  assumes  a 
paler  and  more  delicate  aspect;  its  natural 
secretion  is  also  found  more  sparing.  The 
membrane  is  abundantly  supplied  with 
blood-vessels,  as  well  as  nerves ;  and  also 
possesses  its  share  of  absorbent  vessels. 
Its  arteries,  wliich  ramify  and  anastomose 
so  as  to  form  a  spreading  network  upon  the 
secreting  surface,  are  derived  superiorly 
from  the  lateral  nasal;  inferiorly  from  the 
facial  and  palato-maxillary.  Its  nerves  are 
furnished  by  the  first  and  fifth  pairs. 

"  Sinuses.  —  These  cavities  are  formed  in 
the  interior  of  several  of  the  bones  of  the 
cranium  and  face :  in  fact,  with  the  excep- 
tion of  the  membrane  lining  them,  they  are 
entirely  osseous  in  their  composition.  This 
will  account   for   their   descrijjtion    having 


been  already  given  (at  page  46),  to  which 
we  must  again  refer. 

"  Ducts.  —  There  are  two  ducts  belonging 
to,  or  connected  with,  the  nose.  One  is  the 
diiclus  ad  nasnm  —  a  tube  partly  osseous 
and  partly  membranous  in  its  composition, 
commencing  at  the  inner  angle  or  corner  of 
the  eye,  witliin  the  substance  of  the  lachry- 
mal bone,  running  within  a  canal  continued 
from  this  bone  through  the  superior  maxil- 
lary bone,  and  terminating  at  the  inner  and 
inferior  part  of  the  nasal  fossa,  underneath 
the  duplicature  of  the  inferior  ala,  upon 
the  surface  of  the  common  skin,  about  one- 
fourth  of  an  inch  from  its  junction  with 
the  Schneiderian  membrane,  by  an  orifice 
large  enough  to  admit  a  crow-quill.  The 
other  duct  is  the  ductus  communis  narium, 
which  pursues  its  course  along  underneath 
the  vomer  to  the  pharynx ;  after  arising  from 
two  lateral  branches  springing  from  oblong 
apertures  in  the  floor  of  the  nostrils." 

INTERNAL  PARTS. 

COMPREHENDIXG   THE   CAVITIES  OF   THE  CRANIinW,   OR- 
BIT, NOSE,  AND  MOUTH. 

I. CAVITY    OF    THE    CRANIUM, 

Constructed  for  the  lodgment  of  the 
brain  with  its  appendages,  is  in  form  ovoid, 
flattened  inferiorly,  broader  anteriorly  than 
posteriorly;  its  antero-posterior  or  long 
diameter  measuring  about  seven  inches ;  its 
transverse  or  lateral  diameter  about  four 
inches ;  its  vertical  or  perpendicular  diameter 
about  three  and  a  half  inches.  At  the  same 
time  it  is  to  be  observed,  that,  although  the 
general  form  of  the  cavity  is  the  same,  its  di- 
mensions may  and  do  vary  in  different  heads. 
The  eight  bones  composing  the  cranium  all 
present  internally  surfaces  more  or  less  con- 
cave, which,  united,  form  the  cavity  under 
consideration  ;  hence  it  is  that  the  interior 
is  not  regular  or  uniform,  but  presents  to 
view  different  hollows,  which  are  adapted 
to  distinct  prominences  of  the  cerebral  mass. 

Division  of  the  interior  surface  into  roof 
and  base  of  the  cranium  : 

The  roof  is  formed  by  the  frontal,  parietal, 
and  occipital  bones:  its  superficis  is  larger 


THE   HORSE. 


95 


than  the  extent  of  the  base,  and  it  is  with- 
out any  apparently  defective  places,  observ- 
able in  the  latter.  It  presents  —  1st.  On 
the  mesian  line  from  front  to  back,  the  sagit- 
tal groove,  for  the  longitudinal  sinus  formed 
by  the  frontal  and  parietal  crests,  crossed 
towards  the  front  by  the  coronal  suture,  and 
bounded  posteriorly  by  the  parietal  protu- 
berance, to  which  is  attached  the  tentorium, 
and  behind  which  is  the  occipital  capula,  for 
covering  the  cerebellum.  2nd.  On  either 
side,  alorig  the  same  line,  the  cerebral  con- 
cavities of  the  frontal  bone ;  the  coronal 
suture,  the  boundary  line  between  them 
and  the  parietal  concavities ;  the  transverse 
grooves,  for  the  lateral  sinuses ;  and,  sujik 
within  them,  the  lainbdoidal  suture. 

The  base  is  formed  by  the  temporal, 
sphenoid,  ethmoid,  and  occipital  bones.  It 
presents  —  1st.  On  the  middle  line,  from 
before  backwards,  the  crista  galli,  and  on  its 
sides  the  ethmoidal  fossce  and  cribriform 
plates,  bounded  laterally  by  the  internal 
orbital  plates  of  the  frontal  bones,  and  there 
pierced  by  the  internal  orbital  foramina ;  the 
concave  surface  of  the  body  of  the  ethmoid 
bone;  the  optic  hiatus  leading  to  the  optic 
foramina;  a  transverse  suture  between  the 
ethmoid  and  sphenoid  bones.  Upon  the 
sphenoid  bone,  the  pituitary  fossa,  bounded 
laterally  by  the  two  optic  fossoe ;  the  latter 
leading  to  the  foramina  lacera  orbitalia, 
over  which  are  the  spinal  foramina ;  a  trans- 
verse elevated  line  denotes  the  place  of 
junction  of  the  sphenoid  with  the  occipital 
bone.  Belonging  to  the  occipital  bone,  are 
the  basilar  fosscE  and  the  occipital  hole.  2d. 
On  either  side,  in  the  same  direction,  the  inter- 
nal surface  of  the  wing  of  the  ethmoid  bone, 
rather  more  convex  than  concave,  for  the 
support  of  the  anterior  lobe  of  the  cere- 
brum ;  the  concavity  of  the  iving  of  the  sphe- 
noid bone,  for  the  reception  of  the  middle 
lobe ;  the  concavity  of  the  squamous  part  of 
the  temporal  bone,  for  lodging  the  posterior 
lobe  :  and  the  sutures  bounding  these  three 
cerebral  surfaces.  The  foramen  lacerum 
basis  cranii,  formed  between  the  wing  of 
the  sphenoid  anteriorly,  the  basilar  process 
of  the   occipital   bone  internally,  and   the 


petrous  portion  of  the  temporal  bone  exter- 
nally and  posteriorly :  it  is  wide  and  irregu- 
lar before,  narrow  behind,  and  is  distin- 
guished into  the  spheno-occipital  and  tempo- 
ro-occipital  hiatus.  The  petrous  portion  of 
the  temporal  bone,  presenting  a  narrow 
triangular  surface  forwards  and  upwards, 
which  contributes  to  the  posterior  cerebral 
concavity ;  a  broad,  smooth,  but  uneven  sur- 
face inwards,  against  which  inclines  the 
cerebellum,  and  upon  which  we  distinguish 
—  a,  the  orifice  of  the  meatus  auditorius  in- 
ternus ;  b,  a  transverse  prominence,  and  sev- 
eral cerebral  indentations;  c,  an  irregular 
convexity  downwards,  which  forms  the 
boundary  wall  of  the  labyrinth  ;  d,  a  fissure 
separating  it  from  the  former.  Lastly,  the 
sutures,  uniting  the  petrous  to  the  squamous 
portion  and  to  the  occipital  bone.  Of  the 
occipital  bone  a  part  of  the  internal  surface 
assisting  in  the  formation  of  a  concavity  for 
the  cerebellum,  by  the  convolutions  of  which 
it  is  indented ;  the  surface  even  and  smooth, 
and  slightly  excavated  below  this,  for  the 
support  of  the  medulla  oblongata ;  still 
lower,  the  condyloid  foramina,  through  which 
the  ninth  pair  of  nerves  pass  out. 


II. 


THE    ORBITS 


Two  in  number,  are  formed  for  the  lodg- 
ment, attachment,  and  protection  of  the 
eyes  and  their  appendages. 

Figure.  —  Symmetrical.  The  cavity, 
which  is  extended  horizontally  backward 
and  inward,  has,  viewed  in  front,  a  pyra- 
midal aspect :  the  base,  represented  by  the 
front,  has  four  sides,  and  four  angles ;  one 
only  of  the  sides,  however,  is  sufficient  in 
extent  to  reach  the  apex,  the  others  being 
all  more  or  less  imperfect.  A  line  drawn 
in  a  horizontal  direction  through  the  axis 
of  this  figure,  inclines  more  outwards  than 
forwards,  more  forwards  than  downwards, 
intersecting  another  horizontal  line  projected 
directly  forward  at  an  angle  of  about  70°, 
and  one  extended  laterally,  directly  outward, 
(at  right  angles  with  the  former),  at  about 
20° :  the  incfination  downward,  however, 
will  in  course  vary  with  the  erect  position 
of  the  head. 


96 


ANATOMY    AND    PHYSIOLOGY   OF   THE    IIOESE. 


Structure.  —  The  orbit  is  composed  of 
unequal  portions  coming  from  four  of  the 
bones  of  the  cranium,  and  from  three  of 
those  of  the  face  :  viz.,  the  frontal,  ethmoid, 
sphenoid,  and  temporal  bones;  the  malar, 
lachrymal,  and  palate  bones. 

Division — Into  sides,  angles,  base,  and 
apex. 

Sides.  —  The  superior  side  or  roof  of  the 
cavity  consists  only  of  the  frontal  arch; 
which  is  concave  and  smooth  internally,  to 
make  room  for  the  lachrymal  gland,  and 
has  anterior  and  posterior  borders,  sharp  and 
slightly  curvated.  The  inferior  side  or  floor 
of  the  orbit  is  formed  hy  the  orbital  surfaces 
of  the  lachrymal  and  malar  bones,  is  broader 
than  the  roof,  though,  like  it,  is  deficient  as 
a  whole.  It  comprises  the  orbital  portion 
of  the  lachrymal  suture :  it  is  terminated  in 
front,  hy  a  smooth,  rounded,  curvated  border; 
behind,  nearly  midway  between  the  base 
and  apex,  by  a  shorter  and  straighter  border. 
The  internal  or  nasal  side,  the  broadest  and 
only  complete  one,  is  formed  principally  by 
the  internal  orbital  process  of  the  frontal 
bone,  into  the  notch  of  which  is  received  the 
OS  planum:  the  ethmoid  bone  fm-ther  con- 
tributes, and  also  the  sphenoid  and  palate 
bones,  the  three  constituting  that  irregular 
termination  of  the  cavity '  behind  which 
represents  the  apex.  The  frontal  orbital 
plate  is  smooth  and  slightly  concave,  and  is 
united  below  by  a  continuation  of  the  trans- 
verse suture  with  the  lachrymal  bone.  Its 
border  in  front,  though  slightly  curvated,  is 
very  irregular,  having  several  notches  and 
one  or  two  small  foramina  in  it;  it  also 
presents  a  little  tubercle,  to  which  the  lach- 
rymal caruncle  is  attached.  The  external 
or  zygomatic  side  is  formed  principally  by 
the  zygomatic  process  of  the  malar  bone,  that 
of  the  temporal  contributing  but  little  :  it  is 
concave,  and  smooth  internally,  somewhat 
broader  below  than  upwards  ;  is  intersected 
obliquely  by  the  zygomatic  suture,  and  has 
an  interior  border,  smooth  and  curvated,  a 
posterior  one,  sharp  and  straight. 

Angles.  —  The  supero-internal  angles,  one 
before,  the  other  behind,  are  formed  by  the 
beginning  of  the  frontal  arch,  through  which, 


midway  between  them,  passes  the  supra- 
orbital foramen.  The  infero-internal  angle 
includes  tlie  lachrymal  fossa.  The  supero- 
cxtcrnal  angles,  one  anterior,  the  other  pos- 
terior, are  intersected  by  the  suture  uniting 
the  frontal  and  zygomatic  arches.  The 
infero -external  angles,  particularly  the  ante- 
rior, are  rounded  and  smooth. 

Base.  —  Of  the  circumferent  border,  the 
superior  and  internal  parts,  about  two-fifths 
of  the  entire  circle,  are  formed  by  the  os 
frontis  ;  the  inferior  and  internal  parts,  about 
one-fifth,  by  the  lachrymal  bone ;  and  the 
remaining  two-fifths  by  the  malar  and  tem- 
poral bones,  in  the  proportion  of  three  parts 
of  the  former  to  one  of  the  latter. 

The  apex  or  back  of  the  orbit,  formed  by 
the  ethmoid,  spenoid,  and  palate  bones,  is 
pierced  by  five  foramina :  the  two  round  are 
the  internal  orbital  and  optic,  which  are 
ranged  in  a  row  with  two  oval  and  larger 
in  size,  the  supero-posterior  and  infero-pos- 
terior  orbital;  the  one  behind  is  the  spinal 
foramen. 

III. CAVITIES    OF    THE    NOSE, 

Comprehending  the  nasal  fossae  or  cham- 
bers, and  the  sinuses.  These  cavities  occupy 
about  tsvo-thirds  of  the  internal  space  of 
the  superior  maxilla,  the  remaining  third 
belonging  to  the  cranium  ;  from  which  they 
are  partitioned  by  the  cranial  septum  of  the 
frontal  bone,  in  union  with  the  cribriform 
plates  and  crest  of  the  ethmoid. 

The  nasal  fossae  may  be  said  to  include 
about  two-thirds  of  the  entire  space  de- 
voted to  the  olfactory  cavities.  They  con- 
stitute the  interior  of  the  proboscis ;  have 
four  boundary  walls,  one  above,  one  below, 
and  two  laterally  ;  are  separated  from  each 
other  by  a  septum ;  but  are  open  both  be- 
fore and  behind. 

The  superior  wall  presents  an  irregular 
concave  formed  by  the  internal  surfaces  of 
the  nasal  bones,  the  cells  and  grooves  of  the 
ethmoid,  and  small  portions  of  the  nasal 
surfaces  of  the  palate  bones. 

The  inferior  waU  is  horizontal ;  it  extends 
forward  beyond  the  superior,  but  is  con- 
siderably overreached  by  that  wall  poste- 


THE   HORSE. 


97 


riorly :  it  is  formed  by  the  palatine  por- 
tions of  the  anterior  and  superior  maxillary, 
and  by  the  palate  bones.  The  surface  is 
transversely  concave,  and  presents  a  slight 
eminence  a  little  behind  its  middle. 

Each  lateral  wall  or  side  presents  an 
irregular  concavity,  and  is  formed  by  the 
anterior  and  superior  maxillary  and  the 
palate  bones.  To  it  are  attached  the  supe- 
rior and  inferior  turbinated  bones,  by  which 
the  fossa  is  divided  into  three  separate  pas- 
sages or  meatus.  The  superior  meatus, 
comprised  between  the'  nasal  and  superior 
turbinated  bones,  extends  from  the  angle  of 
the  lateral  nasal  opening,  passing  over  the 
ethmoidal  cells,  to  the  cribriform  plate,  fol- 
lowing superiorly  the  declination  of  the 
wall.  The  middle  meatus,  included  between 
the  turbinated  bones,  leads  superiorly  into 
the  ethmoidal  grooves  and  cells,  and  into 
the  sinuses  of  the  head,  and  ends  below,  be- 
neath the  termination  of  the  superior.  This 
passage,  lUce  the  former  one,  is  narrow ;  but 
its  greatest  diameter  is,  obUquely,  in  the 
perpendicular  direction ;  whereas  the  other 
measures  most  from  side  to  side.  It  re- 
ceives the  apertures  of  the  ductus  ad 
nasum,  maxillary  sinus,  ethmoidal  grooves, 
and  turbinated  cells.  The  inferior  meatus 
is  the  most  capacious  as  well  as  the  most 
direct  one:  it  extends  along  the  inferior 
wall,  from  the  anterior  to  the  posterior 
opening  of  the  nose. 

The  septum  nasi  is  the  partition  separat- 
ing one  fossa  from  the  other.  It  is  formed, 
posteriorly,  by  the  ethmoidal  plate;  infe- 
riorly  and  posteriorly,  by  the  vomer ;  supe- 
riorly and  anteriorly,  (and  principally)  by  a 
broad  perpendicular  plate  of  cartilage. 

The  openings  of  the  nose  are :  the  ante- 
rior, divided  by  the  nasal  peak  and  septum 
nasi  into  two,  and  formed  by  the  superior 
borders  of  the  anterior  maxillary  bones : 
the  posterior,  divided  after  the  same  manner 
by  the  vomer  and  septum,  and  formed  by 
the  nasal  surfaces  and  crescentic  borders  of 
the  palate  bones. 

The  sinuses  of  the  head  communicate 
with,  and  may  be  said  to  constitute'  part  of, 
the  nasal  cavities.     They  are  the  frontal, 

IS 


nasal,  maxillary,  sphenoidal,  ethmoidal,  and 
palatine. 

The  frontal  sinuses,  formed  within  the 
frontal  bones,  are  situated  so  that  a  straight 
line  extended  between  the  supero-internal 
angles  of  the  orbits  passes  opposite  to 
about  the  angular  or  deepest  parts  of  their 
cavities.  The  sinus  (on  either  side)  has  a 
triangular  figure.  The  superior  side  or  roof 
is  flat,  and  (barring  the  septa)  even  upon 
its  surface ;  whereas  the  posterior  side  is 
irregular,  being  convex  inwardly,  where  it 
is  formed  by  the  cranial  septum ;  concave 
outwardly,  where  it  is  opposed  to  the  part 
composing  the  temporal  fossa.  The  infe- 
rior side  slants  from  behind  forward,  and 
from  below  upward,  is  irregular  on  its  sur- 
face, and  open  or  deficient  outwardly, 
where  the  cavity  communicates  with  the 
maxillary  sinus.  Of  the  angles,  one  is 
directed  upward;  another  downward,  ter- 
minating in  the  nasal  sinus,  with  which  it 
is  conjoined,  the  two  forming  one  continu- 
ous cavity ;  the  thu-d  points  backward,  and 
is  directly  opposite  to  the  imaginary  trans- 
verse line  above  alluded  to.  The  cavity  is 
traversed  and  divided  into  several  unequal 
open  compartments  and  recesses  by  septa; 
the  principal  of  which  is  one  extended  be- 
tween the  superior  and  inferior  sides ;  it  is 
partitioned  from  the  opposite  sinus  by  the 
nasal  spine.  The  sinus  is  but  small  in  the 
young  compared  to  its  proportionate  dimen- 
sions in  the  adult  subject:  it  continues  to 
increase  afterwards  with  age,  and  ultimately 
extends  throughout  the  whole  of  the  frontal 
bone. 

The  nasal  sinuses,  formed  by  the  nasal 
bones  above  and  the  superior  turbinated 
bones  behind,  are  nothing  more  than  the 
culs-de-sacs  or  blind  terminations  of  the 
frontal  sinuses. 

The  maxillary  sinuses,  the  largest  of 
these  cavities,  are  spacious  but  very  irregu- 
larly formed.  They  are  situated  below  and 
in  front  of  the  frontal.  Of  this  sinus,  on 
either  side,  the  posterior  and  external  walls 
are  formed  by  the  malar  and  lachrymal 
bones,  whose  orbital  processes  constitute  a 
thin  partition  between  it  and  the  orbit ;  the 


98 


ANATOMY    AND    PHYSIOLOGY    OF 


inferior  parts  consist  of  the  excavations  in 
the  superior  maxillary  bone  ;  snpcn-iorly,  the 
sinus  is  open,  being  there  continuous  with 
the  frontal  :  the  boundary  line  between 
these  cavities  is  marked  by  the  suture 
uniting  the  lachrymal  to  the  frontal  and 
nasal  bones  on  the  outer  side,  and  by  the 
prominent  crest  formed  by  the  junction  of 
the  superior  turbinated  with  the  ethmoid 
bone  on  the  inner  ;  underneath  which  part, 
through  a  curved  (and  in  the  recent  subject 
sort  of  valvular)  fissure,  the  sinus  opens 
into  the  middle  meatus,  between  the  bases 
of  the  turbinated  bones.  The  cavity  is  but 
small,  and  still  more  irregular,  in  the  young 
subject,  in  consequence  of  the  intrusion  of 
the  yet  uncut  molar  teeth. 

The  frontal  sinus,  then,  terminates  in  the 
nasal,  but  both  discharge  themselves  into  the 
maxillary ;  the  maxillary  has  also  a  blind 
termination,  but  empties  itself  into  the  pos- 
terior part  of  the  middle  nasal  meatus. 

The  sphenoidal  sinus  is  situated  within 
the  palatine  portion  of  the  body  of  the 
sphenoid  bone.  It  has  no  existence  in  the 
young  subject,  the  bone  being  solid  through- 
out ;  but  in  process  of  growth  a  cavernous 
hollow  is  formed,  which,  from  the  seces- 
sion and  attenuation  of  the  lamina?  of  the 
bone,  continues  to  enlarge.  It  communi- 
cates, by  two  ovoid  openings,  with  the  eth- 
moidal sinuses. 

The  ethmoidal  sinuses  are  two  cavities, 
separated  by  the  perpendicular  plate,  situa- 
ted beneath  the  ethmoidal  cells.  They 
have  openings  in  front,  communicating  with 
the  lowermost  and  largest  grooves  of  the 
same  bone,  and  with  the  palatine  sinuses. 

The  palatine  sinuses  are  formed  between 
the  superior  maxillary  and  palate  bones  ; 
are  situated  below  and  in  front  of  the  for- 
mer ;  are  separated  from  each  other  by  the 
vomer;  and  open  into  the  maxillary  sinuses: 
they  are  irregular  in  form  and  cavernous 
interiorly.  They  are  not  to  be  found  in  the 
young  subject.  Some  might  be  inclined  to 
treat  them  as  parts  of  the  maxillary  sinuses  ; 
they  are,  however,  as  perfectly  distinct  from 
the  latter  as  the  frontal  are. 


IV. THE    MOUTH. 

The  mouth  is  the  cavity  included  be- 
tween the  superior  and  inferior  maxillse, 
making  (in  the  skeleton)  one  common  va- 
cuity with  the  inter-maxillary  space.  Its 
antero-posterior  dimensions  can  be  but 
little  varied;  but  its  supero-inferior  diame- 
ter will  be  increased  in  the  ratio  of  the  dis- 
tance to  which  the  inferior  maxilla  recedes 
from  the  superior;  the  cavity  during  the 
distraction  of  the  jaws  assuming  the  figure 
of  a  misplaced  t>  ,  the  angle  of  which  is 
turned  backward. 

The  mouth  is  formed  —  superiorly,  by 
the  palatine  and  superior  and  anterior  max- 
illary bones  ;  inferiorly,  by  the  inferior 
maxilla  ;  laterally,  by  the  molar  teeth  ;  an- 
teriorly, by  the  incisive  teeth.  Behind, 
through  the  posterior  opening  of  the  nose, 
it  communicates  with  the  nasal  fossae. 

PERITONEUM.* 

The  whole  of  the  viscera  contained 
within  the  abdomen  proper,  including  the 
anterior  part  of  the  rectum,  bladder,  and 
vasa  deferentia,  are  either  entirely  or  par- 
tially covered  by  or  in  contact  with  perito- 
neum. This  is  a  serous  membrane  reflected 
also  over  the  parietes  of  the  abdomen,  so 
that  a  parietal  and  visceral  or  reflected  por- 
tion require  notice.  Like  other  membranes 
of  the  same  nature,  it  forms  a  closed  sac, 
which,  however,  is  not  the  case  in  the 
female,  as  its  cavity  communicates  with 
that  of  the  uterus,  owing  to  the  open  state 
of  the  FaUopian  tubes  at  their  fimbriated 
edges. 

It  is  loosely  connected  with  the  abdominal 
parietes  by  subserous  cellular  tissue,  and 
the  same  obtains  with  regard  to  its  connec- 
tion with  the  viscera.  But  we  find  some 
parts  more  adherent  than  others,  such  as 
along  the  linea  alba  and  cordiform  portion 
of  the  diaphragm.  Also  on  the  organs  it 
is  but  loosely  connected  with  them  at  their 
attached  border,  where  it  forms  generally  a 
triangular  space,  occupied  simply  by  vessels, 
nerves,  and  cellular  tissue,  and  allowing  of 

*  Prize  Essay  by  Mr.  Gamgec. 


THE    HORSE. 


&9 


their  distention  and  alteration  in  figure. 
On  the  other  hand,  it  is  more  adherent  as 
it  extends  over  the  free  surface  or  margin 
of  the  various  parts  it  is  in  contact  with. 

The  peritoneum  being  considered  as  ex- 
tending from  the  umbilicus  over  the  ab- 
dominal parietes  towards  the  median  line 
of  the  diaphragm  and  spine,  is  found  there 
to  fold  on  itself,  and  proceed  from  the  latter 
on  to  the  intestine,  forming  the  mesenters  ; 
and  from  the  former  on  to  the  liver  and 
stomach,  constituting  ligaments.  These 
folds  of  peritoneum  are  also  seen  extending 
from  organs  to  other  parts  of  the  abdominal 
parietes,  and  these  also  constitute  ligaments. 
Then  they  may  be  traced  from  one  organ 
to  another,  giving  rise  to  the  several  omenta ; 
all  of  which  we  shall  more  especially  allude 
to  as  we  speak  of  the  peritoneal  coat  of 
each  separate  viscus. 

STOMACH. 

The  stomach  is  the  dilated  portion  of 
the  alimentary  canal,  intermediate  between 
the  oesophagus  and  small  intestine:  through 
the  former  it  receives  the  ingested  aliment, 
for  which  it  acts  as  a  reservoir  during  the 
process  of  chymification,  the  active  agent 
in  which  is  the  gastric  secretion. 

In  the  horse,  as  well  as  all  other  soli- 
pedes,  this  viscus  is  exceptional  in  not  being 
the  most  capacious  dilatation  of  the  alimen- 
tary canal.  M.  Colin,  in  a  paper  published 
in  the  Recueil  de  Medecine  Veterinaire 
Pratique  for  June.,  1849,  states  that  the 
capacity  of  the  horse's  stomach  is  very 
variable.  He  says,  that  in  a  very  small 
horse  he  found  it  only  nine  quarts  (accord- 
ing to  his  evaluation  by  litre,  which  may 
be  considered  as  thirty -four  fluid  ounces), 
while  in  one  of  colossal  dimensions  it  was 
as  much  as  33  3-4  quarts,  both  having  died 
at  the  college  (Alfort)  infirmary.  He  gives 
the  average  as  being  from  13  7-20  quarts 
to  14  3-5.  Then,  considering  the  capacity 
of  the  stomach  in  relation  with  that  of  the 
intestines,  he  found  it  in  a  very  small  horse 
as  one  to  thirteen,  while  in  other  two  cases 
it  was  as  one  to  ten.     He  takes  the  latter 


as  the  standard  relative  capacity  between 
the  two. 

The  stomach  is  situated  transversely  to 
the  long  axis  of  the  body,  in  the  left  hypo- 
chondrium,  extending  into  the  epigastrium 
and  during  repletion  into  the  right  hypocon- 
driac  region.  However,  its  size  and  situa- 
tion vary  under  different  circumstances,  as 
to  whether  it  be  full  or  empty,  adapting 
itself  generally  to  its  contents. 

The  stomach  is  fixed  on  its  left  side  to 
the  diaphgram  by  the  oesophagus,  having 
the  spleen  attached  to  it  as  well.  The 
duodenum  then,  by  means  of  the  lesser  or 
gastro-hepatic  omentum,  suspends  the 
pyloric  end  by  getting  attached  to  the  con- 
cave surface  of  the  liver. 

The  shape  of  the  stomach  might  be  ex- 
pressed as  being  that  of  a  tube  bent  on 
itself,  and  dilated  along  its  convex  border, 
so  as  to  form  two  cul-de-sacs ;  i.  e.,  a  right 
and  a  left  one,  whilst  it  has  two  borders  or 
curvatures,  distinguished  as  a  lesser  concave 
and  a  greater  convex  one.  The  stomach 
has  two  smooth  surfaces,  the  anterior  one 
being  in  contact  with  the  liver  and  dia- 
phragm, whilst  the  posterior  one  corresponds 
to  the  convolutions  of  the  small  intestines 
and  gastric  flexture  of  the  colon.  It  has 
two  orifices,  i.  e.,  a  left  oesophageal,  or  com- 
monly called  cardiac,  and  a  right  intestinal 
or  pyloric  one ;  the  latter  taking  its  name 
from  the  valve  by  which  it  is  guarded. 

A  circular  depression  round  the  stomach, 
midway  between  the  cardiac  and  pyloric 
orifices,  most  visible  when  the  organ  is 
replete,  marks  the  external  division  of  the 
stomach  into  a  cardiac  and  pyloric  portion, 
corresponding  with  the  point  where  the 
mucuous  membrane  varies  in  character  in- 
ternally. The  sacular  projection  at  the 
cardiac  portion  takes  the  name  of  fundus, 
owing  to  its  greater  magnitude  as  compared 
with  a  smaller  cul-de-sac  at  the  pyloric  end, 
the  analogue  of  which  in  human  anatomy 
is  characterized  by  the  appellation  of  antrum 
pylori. 

Having  thus  briefly  described  the  striking 
peculiarities    of    the    stomach,    I   proceed 


100 


ANATOMY  AND   PHYSIOLOGY   OF 


with  more  detail  to  the  consideration  of 
its  constituent  parts,  such  as  its  coats, 
nerves  and  vessels. 

The  coats  of  the  horse's  stomach  having 
been  generally  described  as  four,  it  appears 
needless  to  alter  their  nomenclature,  although 
the  one  which  I  shall  allude  to  as  third 
might  quite  as  justly  be  described  as  second, 
or  merely  spoken  of  as  connecting  cellular 
tissue,  without  regarding  it  as  a  separate  coat. 

The  external  peritoneal  tunic  is  found 
proceeding  from  the  diaphragm  on  to  the 
cardiac  portion  of  the  stomach,  surrounding 
the  oesophageal  opening,  where  it  is  tough, 
and  forms  the  gastro  phrenic  ligament.  Thus 
we  follow  it  on  to  the  corresponding  surface 
of  the  viscus,  and,  firstly,  more  especially 
on  to  the  lesser  curvature,  where  it  is  loosely 
connected  with  the  other  coats,  and,  the 
middle  portion  being  more  adherent,  gives 
rise  to  two  folds  laterally,  which  seem  to 
stretch  from  the  cardiac  to  the  pyloric  orifices, 
to  bind  the  two  together,  necessarily  leaving 
a  pit  or  cul-de-sac  between  them.  At  the 
pyloric  end  the  peritoneum  comes  off  from 
the  concave  surface  of  the  liver  on  to  the 
stomach,  constituting  the  gastro-hepatic  or 
lesser  omentum,  the  anterior  layer  of  which 
comes  from  the  anterior  part  of  the  concave 
surface  of  the  liver,  whUst  the  posterior 
layer  comes  from  the  posterior  part  of  the 
same,  so  that  the  two  enclose  the  vessels 
going  to  and  from  the  porta. 

Having  formed  a  covering  to  the  corres- 
ponding surface  of  the  stomach,  the  layers 
of  peritoneum  meet  at  the  greater  curvature. 
In  following  them  from  this  point  the  des- 
cription will  be  facilitated  by  alluding  to 
the  two  separately,  as  they  meet  to  form 
the  gastro-splenic  and  gastro-colic  omenta, 
as  well  as  the  omental  sac.  In  forming 
the  latter,  they  so  blend  as  merely  to  con- 
stitute a  fine  reticulated  vascular  layer,  in- 
separable into  t^vo,  except  near  the  magins 
of  the  viscera.  Distinguishing  the  anterior 
or  external  layer  as  A,  and  the  posterior  or 
internal  one  as  B,  their  arrangement  admits 
of  exposition  in  the  following  terms  :  — 

A  passes  from  the  anterior  surface  of  the 
stomach,  forms  the  loose  omentum,  and  gets 


on  to  the  transverse  colon  and  spleen. 
Reaching  the  latter,  it  is  reflected  over  its 
superior  surface  at  the  posterior  margin  of 
the  bilus,  so  as  to  contribute  to  the  form- 
ation of  the  gastro-spleijic  omentum,  and 
extends  round  the  free  posterior  margin  of 
the  viscus  on  to  the  inferior  surface,  passing 
to  the  right  on  to  the  left  kidney,  and, 
anteriorly  reaching  the  supero-anterior  part 
of  the  spleen,  is  reflected  from  it  so  as  to 
continue  as  the  outer  layer  of  the  loose 
omentum.  Further  to  the  right,  A  is  trace- 
able on  to  the  inferior  surface  of  the  trans- 
verse colon,  and,  extending  round  the  pos- 
terior part  of  the  latter,  is  found  to  ascend 
up  to  the  spine,  and  then  turn  backward 
and  downward  to  form  the  mesentery. 

B,  or  the  internal  layer  of  peritoneum, 
passes  from  the  posterior  surface  of  the 
stomach  till  it  reaches  the  infero-anterior 
border  of  the  transverse  colon,  as  well  as  the 
hilus  of  the  spleen.  After  covering  the  an- 
terior surface  of  the  colon,  it  ascends  up  to 
the  pillars  of  the  diaphragm  clothing  the 
anterior  part  of  the  pancreas,  which  is  thus 
held  between  A  and  B,  or  layers  of  the  trans- 
verse meso-colon.  A  little  to  the  left  of  this, 
B  passes  on  to  the  anterior  margin  of  the 
hilus  of  the  spleen,  forming  the  inner  or  pos- 
terior layer  of  the  gastro-splenic  omentum. 

From  this  arrangement  it  results  that  the 
peritoneum,  in  forming  the  lesser  or  gastro- 
hepatic,  the  greater  or  gastro  colic,  and  the 
gastro-splenic  omenta,  closes  in  a  space 
termed  the  omental  sac,  the  interior  of 
which  is  inaccessible  except  by  an  opening 
at  the  posterior  part  of  the  gastro  hepatic 
omentum,  whose  free  margin  at  the  right 
side  marks  the  point  where  it  may  be  pene- 
trated ;  this  passage  is  termed  the  foramen 
of  Winslow.  It  is  bounded  anteriorly  by 
the  lesser  omentum,  above  by  the  liver,  and 
posteriorly  by  the  transverse  colon. 

Thus,  supposing  the  inner  layer  of  the 
omental  sac  to  be  separable  from  the  outer, 
and  drawn  out  through  the  foramen  of 
Winslow,  the  following  parts  would  be  de- 
prived of  peritonaeum,  i.  e.,  the  posterior 
surface  of  the  stomach,  the  gastro  splenic 
omentum  of  its  posterior  layer ;  so  that  the 


EXPLANATION   OF   FIGURE  XI. 


MUSCULAR  STEUCTUEE. 

a".  Trapezius. 

6".  Ehomboideus  longus. 

5.  Splenius. 
c".  Scalenus. 

e".  Pectoralis  parvus. 

/".  Antea  spinatus. 

g".  Postea  si^inatus. 

h".  Teres  major. 

i".   Latissimus  dorsi. 

J".  A  portion  of  the  serratus  magnus. 

k".  "  Humero  cubital." 

I",  m".  «".  Triceps  extensor  brachii :  magnum,  medium,  et  parvium. 

o".  Pectoralis  transversus. 

p.    Flexors. 

2".  Flexor  metacarpi  extemus. 

r".       "  "         internus. 

s".  Extensor  metacarpi  magnus. 

x".  Extensor  pedis. 

a\   Serratus. 

c\    Obliquus  extemus  abdominis. 

d\  Obliquus  internus  abdominis. 

g*.  Region  of  the  patella. 

li\  i.  Glutei  muscles. 

m\  Tensor  vagina. 

11'.  Rectus. 

0'.  Vastus  externus. 

q*.  Flexor  metatarsi. 

?•'.  Gastrocnemius  externus. 

t\   Flexor  pedis  accessorius. 

w.    Sterno  maxillarius. 

V.    Internal  part  of  the  levator  humeri. 

y\  Peroneus. 

x'.  Extensor  pedis. 

33.  Radius. 

J\  Triceps. 

VEINS; 

3.  Jugular  vein. 

4.  Subcutaneous  thoracic  vein. 

6.  Saphena  vein. 
6.  Radial  vein. 

D.   Serratus  magnus  muscle. 

OSSEOUS  STRUCTURE. 


d. 

Dorsal  spines, 

/• 

Uhiar. 

c.  c. 

Fibula. 

16. 

True  ribs. 

17. 

False  ribs. 

18. 

Sternum. 

19. 

Ileimi. 

22. 

Femur. 

23. 

Patella. 

24. 

Tibia. 

34. 

Os  humeri. 

35. 

Radius. 

THE  HOESE. 


101 


vessels  going  to  and  from  the  stomach  and 
spleen  would  remain  uncovered,  the  anterior 
part  of  the  transverse  colon,  the  anterior 
surface  of  the  pancreas,  and  inner  or  pos- 
terior layer  of  the  gastro  hepatic  omentum. 

Next  to  be  described  to  the  serous  coat 
is  the  muscular  one,  which  is  constituted  of 
involuntary  plain  fibres,  whose  thickness  is 
very  variable  in  different  subjects,  as  well  as 
in  different  parts  of  the  same  stomach. 
The  cardiac  end  is  more  muscular  than  the 
pyloric,  except  at  the  right  margin  of  the 
latter,  where  it  is  very  powerful  and  thick, 
as  it  smTounds  the  pylorus.  The  thinnest 
part  of  the  stomach  is  unquestionably  the 
convex  border  of  the  lesser  cul-de-sac. 

The  muscular  coat  of  the  stomach  is  in- 
tricately arranged,  and  authorities  differ 
vastly  from  each  other  in  the  description  of 
the  several  layers  constituting  it.  The 
number  of  layers  entering  into  its  compo- 
sition is  three :  the  outer  and  inner  ones  are 
mostly  continuations  of  the  inner  layers  of 
the  cEsophagus,  while  the  middle  one  is  pro- 
per to  the  stomach. 

The  outer  layer  is  composed  of  the 
longitudinal  fibres  of  the  oesophagus :  as 
these  reach  the  cardiac  end  of  the  stomach, 
they  form  a  peculiar  turn,  whereby  the  dis- 
tribution on  the  surfaces  as  a  flat  layer  is 
facilitated.  Some  of  the  fibres  of  this  layer 
dip  down  to  join  the  deeper  ones,  while 
others  continue  onwards  as  the  longitudinal 
fibres  of  the  duodenum.  As  to  the  fibres 
which  proceed  on  to  the  curvatures,  they 
are  not  so  intricate,  as  they  descend  directly 
from  the  portion  of  the  oesophagus  opposite 
the  part  they  supply,  so  that  the  only  alter- 
ation in  direction  is  that  of  diverging  a  lit- 
tle from  each  other,  and  pursuing  the  bent 
course  of  the  corresponding  gastric  curva- 
ture. On  the  lesser  one  they  soon  become 
scanty,  and  are  lost  in  the  circular  fibres  of 
the  body  of  the* stomach  :  very  few  of  them 
are  traced  on  to  the  pylorous.  The  fibres 
proceeding  on  to  the  greater  cm'vature  are 
mingled  with  other  considerable  bundles 
taking  the  same  direction,  but  which  are  not 
traceable  on  to  the  oesophagus,  as  they  seem 
to  pass  round  each  side  of  the  cardia,  and 


blend  with  the  circular  fibres  on  the  lesser 

curvature. 

The  middle  layer  consists  of  annular 
fibres,  which,  though  scanty  as  they  encircle 
the  extreme  left  end  of  the  stomach,  increase 
in  bulk  towards  the  middle  part  of  the 
organ,  and  are  especially  developed  at  the 
lesser  curvature.  They  again  decrease  over 
the  antrum  pylori,  but  are  ultimately  greatly 
developed  for  the  formation  of  a  powerful 
sphincter  at  the  pylorus. 

The  internal  or  oblique  fibres  of  the 
stomach  have  somewhat  the  same  arrange- 
ment as  the  deep  layer  of  fibres  of  the 
oesophagus,  although  not  perfectly  identical, 
as  they  are  arranged  like  hoops  placed  one 
within  the  other ;  but  while  in  the  former 
the  one  set  enters  the  other  without  inter- 
section, in  the  latter  there  is  a  partial  decus- 
sation by  separate  bundles.  Thus,  in  real- 
ity, the  oblique  fibres  of  the  stomach  are 
constituted  of  two  layers,  the  one  proceed- 
ing from  the  left  end  of  the  stomach  on  to 
the  right,  which  pass  internally  to  the  next 
layer :  this  one  proceeds  from  the  right  of 
the  cardia  on  to  the  fundus.  Owing  to  the 
scantiness  of  circular  fibres  at  the  base  of 
each  cul-de-sac,  the  fibres  are  here  in  con- 
tact with  the  superficial  longitudinal  ones. 
The  oblique  fibres  are  best  studied  by  dis- 
secting from  within,  and,  after  removing 
these,  the  circular  fibres  come  into  view 
with  greater  case  than  by  attempting  to 
expose  them  from  without. 

The  third  coat  of  the  stomach  consists 
merely  of  the  cellular  tissue  existing  be- 
tween the  muscular  and  mucus  coats,  as 
well  as  connecting  the  former  to  the  outer 
serous  tunic,  in  which  case  it  is  more  abund- 
ant and  firm  nearest  the  curvatures.  There 
it  is  situated  between  the  muscular  and  mu- 
cus coats :  it  was  named  by  the  ancients, 
on  account  of  its  white  aspect,  the  Tunica 
Nervosa.  It  is  loose  in  some  parts  and 
firm  in  others ;  not  only  serving  to  connect 
parts  together,  but  also  to  form  a  medium 
in  which  vessels  ramify  for  the  supply  of 
the  organ. 

The  internal  or  mucus  coat  of  the  stom- 
ach differs  in  the  cardiac  from  the  pyloric 


102 


ANATOMY  AND   PHYSIOLOGY   OP 


end,  as  in  the  former  it  is  but  a  mere  con- 
tinuation of  the  unmodified  mucus  lining 
of  the  oesophagus,  being  characteristic  for 
its  scantiness  in  gland  and  but  limited  sup- 
ply of  blood.  The  most  marked  feature  it 
possesses  is  that  of  being  covered  by  a  cuti- 
cular  layer  of  extreme  thickness,  easily 
separable  from  the  basement  structure  be- 
neath after  slight  maceration  or  boiling. 
The  cardiac  portion  of  the  gastric  mucus 
lining  is,  in  a  healthy  stomach,  of  a  dirty 
white,  bedewed  by  more  or  less  mucus, 
and  thrown  into  folds  which  have  a  radiated 
arrangement  at  the  cardiac  orifice,  whilst  at 
the  fundus  they  are  concentrically  arranged. 
This  portion  of  the  membrane  is  also  fur- 
nished with  papillae ;  and  Sprott  Boyd,  in 
an  Inaugural  Essay  on  the  structure  of  the 
Mucus  Membrane  of  the  Stomach,  pub- 
lished in  the  Edinburgh  Medical  and  Surgi- 
cal Journal  for  1836,  describes  a  very  marked 
peculiarity  of  an  interposed  layer  between 
the  epithelium  and  papiilated  surface  of  the 
mucus  lining.  This  intermediate  layer,  he 
says,  has  a  smooth  equal  surface,  perforated 
by  numerous  foramina  about  the  600th  of 
an  inch  in  diameter,  or  perhaps  a  little 
smaller,  the  margins  of  which  are  slightly 
thickened.  He  afterwards  states  that  he 
has  not  been  able  to  trace  in  the  epithelium 
of  any  other  animal  a  structure  similar  to 
that  existing  in  the  horse.  These  peculiar- 
ities in  the  left  pouch  of  the  stomach  cease 
abruptly  midway  the  length  of  the  viscus, 
where  the  cuticular  lining  terminates  by  a 
serrated  edge. 

The  mucus  lining  of  the  right  end  of 
the  stomach  is  normally  of  a  reddish  color, 
and  presents  a  villous,  glistening  aspect, 
coated  thicldy  with  mucus,  and  also  pos- 
sessing a  high  degree  of  vascularity ;  the 
epithelium  is  here  scanty,  but  nevertheless 
tabular.  The  villous  appearance  above 
referred  to  suggests  itself  also  when  the  sur- 
face is  examined  by  the  naked  eye  and  by 
the  aid  of  a  lens ;  but  it  is  deceptive,  as 
has  been  already  remarked  by  Sprott  Boyd, 
who  correctly  refers  it  to  the  raised  margins 
of  the  arolaB  which  stud  the  surface.  This 
portion  of  the  gastric  mucus  membrane  is 


also  thrown  into  folds,  which  become  grad- 
ually more  marked  towards  the  pylorus; 
whereas  they  arc  susceptible  of  obliteration 
by  distention,  there  is  one  circular  fold  at 
the  pylorus  which  is  permanent,  and  so  dis- 
posed as  to  fulfil  the  office  of  a  valve. 

The  arteries  of  the  stomach  are  derived 
from  the  coeliac  axis,  whose  three  divisions, 
i.  e.  gastric,  hepatic,  and  splenic,  all  contri- 
bute to  supply  blood  to  the  viscus ;  but  the 
first  is  specially  destined  to  that  office.  The 
gastric  artery,  being  the  smallest  of  the 
three  divisions,  takes  a  course  downwards, 
forwards,  and  rather  to  the  right,  across  the 
pancreas,  getting  between  the  layers  of  the 
gastro-hepatic  omentum.  Being  then  di- 
rected to  the  left  towards  the  lesser  curva- 
ture, it  divides  into  an  anterior  left  or  smaller 
branch,  and  a  posterior  right  and  more 
capacious  as  well  as  longer  one.  The  an- 
terior division  is  destined  to  supply  the 
anterior  surface  of  the  stomach,  and  more 
especially  the  left  cul-de-sac,  anastomos- 
ing with  branches  (sometimes  called  vasa 
breva),  coming  on  to  the  stomach  from  the 
splenic.  This  division  of  the  gastic  also 
anastomoses  with  oesophageal  twigs,  which 
are  occasionally  of  considerable  size.  The 
posterior  or  right  division  of  the  gastric 
artery,  destined  for  the  pyloric  end  of  the 
stomach,  anastomoses  with  some  splenic 
branches,  but  more  especially  with  the  py- 
loric branches  of  the  hepatic  artery. 

The  veins  returning  the  blood  from  the 
stomach  are  the  gastric  and  splenic,  which 
anastomose  with  the  duodenal  veins.  These 
aU  have  a  few  valves,  but  they  may  be  easily 
injected  from  the  porta  into  which  they 
empty,  owing  to  their  very  free  anastomosis. 

The  lymphatics  of  the  stomach  are  nu- 
merous, and  in  some  parts  very  apparent, 
entering  the  lymphatic  glands  situated  along 
the  greater  curvature  and  around  the  cardia, 
where  they  are  numerous  and  large. 

The  stomach  is  supplied  with  nerves 
from  both  the  cerebro  spinal  and  sympathetic 
or  ganlionic  system.  The  pneumogastric 
or  par  vagna  nerves,  arising  from  the  me- 
dulla oblongata,  are  the  main  conductors 
of  nervous  influence  to  and  from  that  vis- 


THE  HOESE. 


103 


cus.  Their  arrangement  is  simple,  as,  after 
they  have  formed  various  plexuses  within 
the  thorax,  in  which  they  mutually  inter- 
change fibres,  they  reach  the  diaphragm, 
and  here  are  arranged  as  two  nervous 
branches,  i.  e.,  a  superior  and  an  inferior 
one.  The  former  is  principally  destined  for 
the  fundus,  whilst  the  latter  supplies  the 
pyloric  end,  and  sends  branches  off  to  the 
duodenum,  with  one  or  two  to  the  solar 
plexus. 

The  sympathetic  fibres,  destined  for  the 
stomach,  are  derived  from  the  solar  plexus, 
descending  on  to  the  viscus,  in  company 
with  the  vessels. 

INTESTINE. 

This  term  is  applied  to  that  portion  of 
the  alimentary  canal  extending  between  the 
pylorus  and  anus,  destined  for  the  temporary 
retention  of  the  chymous  mass,  so  that 
its  nutrient  parts  may  be  absorbed,  whilst 
its  more  solid,  indigestible  constituents,  are 
collected  for  excretion. 

The  intestine  in  all  monogastria,  but  es- 
pecially in  solipeda,  occupies  by  far  the 
greatest  part  of  the  abdominal  cavity.  The 
bonds  of  attachment  to  the  various  parts  of 
the  latter  are  contracted  by  the  intestine, 
through  its  peritoneal  investment,  more 
especially  to  the  spine,  constituting  mesen- 
ters,  which  I  shall  especially  allude  to  when 
describing  with  more  detail  each  portion  of 
this  capacious  tube. 

Not  only  the  attachments,  but  also  the 
shape  of  the  intestine,  vary  at  different  parts 
of  its  course,  so  that  it  has  been  deemed 
necessary  to  divide  it,  either  arbitrarily  or  at 
natural  demarcations.  Thus  we  speak  of 
the  small  and  large  intestine,  the  two  being 
separated  naturally  by  a  marked  change  in 
direction,  size,  and  confirmation. 

It  is  also  obvious  that,  as  the  situation,  at- 
tachment, and  shape  of  each  portion  of  the 
intestinal  canal  differ,  so  must  the  relations 
be  equally  distinct,  and  further  mention  of 
them  will  therefore  be  reserved  for  fuller 
exposition  elsewhere. 


SMALL    INTESTINE. 

This,  the  smallest  although  longest,  is 
also  the  fij-st  portion  of  the  intestinal  tube, 
extending  from  the  pylorus  to  its  sudden 
termination  into  the  large  intestine.  In  it 
the  chymified  mass  is  subjected  to  the  modi- 
fying influence  of  important  secretions, 
whereby  its  nutritive  parts  are  fitted  for 
absorption  by  the  vessels,  which,  for  this  pur- 
pose, are  arranged  in  this  portion  of  the  in- 
testinal track. 

The  smaU  intestine  has  been  divided  into 
three  parts:  this  classification  is,  however, 
purely  conventional.  Since  it  does  not 
recognize  anatomical  differences  for  its  basis, 
it  might  justly  be  presumed  that  this  dis- 
tinction of  human  anatomists  exhibited 
traces  of  imperfection,  even  when  applied 
to  the  frame  of  man.  Such  being  the  case, 
it  is  no  matter  of  surprise  that,  in  referring 
the  distinction  to  the  intestinal  canal  of 
animals,  the  incongruities  of  the  system 
should  be  still  more  apparent. 

Extending  from  the  pylorus,  the  first  por- 
tion is  termed  the  duodenum,  from  its  being 
considered  as  twelve  fingers'  breadth  in 
length :  it  is,  however,  extended  round  to 
the  left  side  of  the  spine,  posteriorly  to  the 
anterior  mesenteric  artery.  The  middle,  or 
floating  portion  of  gut,  takes  the  name  of 
jejunum,  and  the  third,  or  csecal  portion,  is 
distinctively  designated  ileum. 

The  duodenum  forms  a  wide  curve  from 
the  pylorus  round  to  the  right,  being  situated 
under  the  concave  surface  of  the  liver,  pass- 
ing above  the  transverse  colon,  so  as  to 
attain  the  posterior  part  of  the  mesentery, 
and,  reaching  the  left  side  of  the  spine, 
comes  in  contact  with  the  colon,  where  it  is 
said  to  end  in  the  jejunum.  The  duodenum 
is  fixed  by  the  gastro-hepatic  omentum  to 
the  concave  surface  of  the  liver,  the  layers 
of  which  enclose  the  biliary  and  pancreatic 
ducts,  whereby  this  bond  of  union  is  still 
further  strengthened.  The  peritoneum  com- 
ing from  the  right  and  spigelian  lobes  of  the 
liver,  as  well  as  from  the  right  kidney,  forms 
a  loose  attachment  for  the  duodenum  by 


104 


ANATOMY  AND  PHYSIOLOGY  OP 


extending  on  to  the  hepatic  flexure  of  the 
colon,  after  it  has  surrounded  the  first-named 
gut.  The  next  portion  of  intestine  is  at- 
tached to  the  spine  transversely  to  the  long 
axis  of  the  body  ;  winding  round  the  mes- 
entery to  the  left  of  the  aorta,  it  gets  at- 
tached to  the  gastric  flexure  of  the  colon, 
and  here  it  proceeds,  under  the  name  of 
jejunum,  along  the  free  borders  of  the 
mesentery. 

As  to  the  shape  of  the  duodenum,  from 
the  pylorus  to  the  right  of  the  porta,  we 
find  its  dimensions  so  very  great  as  to  have 
suggested  to  the  ancients  the  similitude  be- 
tween it  and  the  stomach,  of  which  they 
regarded  it  in  some  degree  as  an  analogue, 
as  testified  by  the  appellation  "  Ventriculus 
Succenturiatus,"  given  to  it  by  them.  Fur- 
ther from  the  pylorus,  we  find  it  constricts 
and  assumes  a  certain  caliber,  which  it 
maintains  till  it  loses  its  name  for  that  of 
jejunum. 

With  reference  to  the  relations  of  the 
duodenum,  it  may  be  stated  that  they  ad- 
mit of  detail  on  account  of  the  fixedness 
of  that  portion  of  the  gut,  an  attribute  with 
which  it  is  endowed  in  contradistinction 
to  the  jejunum  and  ileum.  In  the  first 
portion  of  its  course,  i.  e.,  from  the  py- 
lorus to  the  posterior  part  of  the  right 
lobe  of  the  liver,  the  duodenum  by  its 
upper  surface  is  in  contact  with  the  con- 
cave surface  of  the  latter  organ,  crossing 
the  vena  portee,  near  w^hich  it  is  pierced  by 
the  billiary  and  pancreatic  ducts,  which 
enter  it  at  about  five  or  six  inches  from  the 
pylorus,  forming  an  acute  angle  with  each 
other.  The  inferior  surface  of  the  duo- 
denum rests  on  the  transverse  colon,  and 
its  superior  margin  is  in  close  contact  with 
the  anterior  part  of  the  head  of  the  pan- 
creas. 

Round  to  the  right,  the  duodenum  is  in 
contact  with  the  hepatic  flexure  of  the 
colon,  right  and  Spigalian  lobes  of  the  liver, 
as  well  as  the  right  kidney.  To  reach  the 
spine  it  has  to  cross  the  direction  of  the 
right  flexure  of  the  colon,  getting  behind 
the     mesentery  and  gastric  flexure  of  the 


colon,  where  it  is  connected  with  the  left 
kidney. 

Alluding  next  to  the  general  anatomical 
facts  as  applied  to  the  jejunum,  so  caUed 
on  account  of  its  usual  vacuity  after  death, 
the  limit  between  it  and  the  ileum  is  de- 
fined by  imagining  the  small  intestine,  with 
the  exception  of  the  duodenum,  divided 
into  five  equal  portions,  of  which  the  first 
two  take  the  name  of  jejunum,  whilst  the 
last  three-fifths  receive  that  of  ileum. 

The  jejunum  is  suspended  superiorly 
from  the  spine  by  an  extensive  fold  of  per- 
itoneum, termed  mesentery,  which  serves 
also  as  a  medium  for  the  passage  of  the 
mesenteric  arteries,  veins  and  nerves,  as  well 
as  for  chyliferous  vessels,  to  take  their 
course  towards  the  receptaculum  chylo,  sit- 
uated to  the  left  of  the  aorta. 

The  width  of  the  jejunum  is  far  from 
being  uniform,  it  being  more  constricted  at 
some  points  than  at  others:  its  narrowest 
part  is  that  which  is  contiguous  to  the 
ileum. 

The  ileum  is  the  terminating  portion  of 
the  small  intestine,  so  called  from  the  tor- 
tuous course  it  takes,  emptying  itself  into 
the  large  intestine  at  the  junction  of  the 
CEecum  and  colon,  by  an  orifice  provided 
with  a  valve. 

The  first  portion  of  the  ileum  is  simply 
attached  by  mesentery  to  the  spine ;  but, 
in  addition  to  this,  in  the  last  ^art  of  its 
course,  the  gut  is  connected  with  the  csBum 
by  a  fold  of  peritoneum,  which  is  not  large 
enough  to  prevent  them  deviating  more 
than  an  acute  angle  from  each  other. 

The  ileum  is,  on  the  whole,  the  narrow- 
est portion  of  the  small  intestine,  but  the 
thickest  in  its  coats. 

Having  now  especially  to  describe  the 
structure  of  the  small  intestine,  it  may  be 
taken  as  a  whole,  merely  alluding  to  local 
peculiarities. 

This  portion  of  the  alimentary  canal  has 
four  coats,  to  be  described  in  the  same 
order  by  those  of  the  stomach,  i.  e.  peri- 
toneal, muscular,  cellular,  and  internal 
mucus. 


THE  HOESE. 


105 


The  first,  or  the  peritoneal,  has  nothing 
peculiar,  beyond  its  enclosing  a  little  trian- 
gular space  all  along  the  upper  attached 
border  of  the  gut.  The  looseness  of  the 
peritoneal  folds  attaching  the  small  intes- 
tine is  very  marked;  and  Colin  (Soc.  cit.) 
notes,  that  the  mesentery  is  proportionately 
larger  in  young  than  in  adult  quadrupeds, 
so  that  the  gradual  shortening  of  this  ex- 
plains the  spontaneous  reduction  of  exom- 
phalus  or  umbiKcal  hernia. 

The  second,  or  muscular  coat,  is  mostly 
developed  at  the  commencement  of  the 
duodenum  and  terminating  portion  of  the 
ileum.  It  consists  of  white  involuntary 
fibres,  arranged  so  as  to  form  an  outer 
longitudinal  layer,  and  an  inner  cu'cular  one, 
both  of  which  completely  encircle  the  gut. 

The  third,  or  cellular  coat,  is  similar  to 
that  of  the  stomach,  in  being  disposed  in 
two  layers,  so  as  to  connect  the  three  coats 
together.  It  is  especially  condensed  on  the 
inner  surface  of  the  muscular  coat,  so  as  to 
take  the  appearance  of  a  fibrous  tunic,  at- 
tached to  the  mucus  lining  by  loose  cel- 
lular tissue. 

The  fourth,  or  mucus,  coat  is  thin,  hav- 
ing a  velvet  appearance,  due  to  villi,  pecu- 
liarly smaU  in  the  intestines  of  the  horse, 
but  remarkably  developed  in  other  animals, 
especially  carnivora  and  fishes.  The  villi 
may  be  seen  by  a  pocket  lens,  on  a  well- 
washed  piece  of  intestinal  mucus  mem- 
brane, and  between  them  are  seen  numer- 
ous foramina,  which  are  the  openings  of 
tubular  glands,  known  as  the  crypts  of  Lie- 
berkuehn. 

In  addition  to  the  tubular  glands,  by  dis- 
secting, from  without,  the  muscular  from 
the  mucus  coat,  lining  the  commencement 
of  the  duodenum,  we  find  clusters  of  vesi- 
cles, similar  to  the  vesicular  structure  of  the 
salivary  and  pancreatic  glands.  These 
form  distinct  layers,  provided  with  ducts, 
which  open  on  the  free  surface  of  the  mem- 
brane ;  and  Dr.  Todd  states  that  Brunner's 
glands,  or,  as  he  calls  them,  the  duodenal, 
are  more  developed  in  the  horse  than  in  any 
other  animal  he  has  hitherto  examined  them 


in. 


We  have  next  to  treat  of  the  solitary 
glands  —  glandulae  solitarias  —  peculiar  and 
rather  scanty  bodies,  visible  at  various  parts 
of  the  small  intestine.  These  are  vesicu- 
lar, and  without  any  opening  when  in  the 
perfect  state,  surrounded-  by  villous  pro- 
cesses and  Lieberkuehnian  follicles.  Some 
of  the  villi  also  project  from  the  surface  of 
the  so-called  glands,  which  are  most  ap- 
parent when  distended  with  secretion. 

About  the  second  half  of  the  jejunum, 
and  along  the  whole  of  the  ileum,  we  see 
longitudinal  patches,  varying  from  half  an 
inch  to  even  three  inches  in  length,  scat- 
tered all  over,  but  more  especially  situated 
near  the  superior  or  attached  border  of  the 
small  intestine,  which  is  contrary  to  the 
faulty  description  of  some  recent  authors. 
These  patches,  distinguished  as  Peyer's 
glands  or  patches,  also  as  Agminated  glands 
—  GladdulaB  agminatse  seu  aggregatae — con- 
sist of  an  accumulation  of  small  bodies,  each 
resembling  a  glandula  solitaria  in  miniature, 
being  also  destitute  of  a  natural  aperture. 
Colin  (loc.  cit.)  states  that  they  are  first 
seen  at  a  distance  of  about  six  feet  and  a 
half  from  the  pylorus,  and  the  least  num- 
ber of  them  he  has  ever  counted  has  been 
102,  whilst  the  utmost  has  been  158. 

The  mucus  membrane  of  the  small  in- 
testine is  thrown  into  folds,  at  different 
parts,  which  are  transverse,  and  scalloped 
near  the  pylorus,  whilst  in  other  parts  they 
are  mostly  longitudinal ;  these  are  all  tem- 
porary folds.  There  is  no  such  arrange- 
ment as  the  valulas  conniventes  in  the  small 
intestines  of  the  horse,  though  recent  wri- 
ters of  great  eminence  have  described  them. 
About  five  inches  from  the  pylorus,  at 
the  superior  border  of  the  duodenum,  is  a 
semicircular  fold,  which,  if  elevated,  ad- 
mits of  the  finger  being  thrust  behind  it 
into  the  wide  biliary  duct.  The  opening 
of  the  pancreatic  duct  is  also  visible  beneath 
this  fold,  but  it  is  not  so  capacious  as  the 
one  last  mentioned. 

LARGE    INTESTINE. 

The  large  intestine  constitutes  the  termi- 
nating   portion   of   the   alimentary   canal, 


14 


106 


ANATOMY   AND   PHYSIOLOGY   OP 


being  remarkably  more  developed  in  soli- 
pedes  than  in  any  other  of  our  domestic 
quadrupeds.  It  occupies  the  greater  part 
of  the  abdomen,  and  most  of  it  is  loose, 
whilst  its  shape  and  other  peculiarities  vary 
considerably  at  diflerent  points. 

It  is  divided  into  three  parts  —  caecum, 
colon,  and  rectum  —  the  precise  extent  of 
each  being  defined  by  special  anatomical 
characters. 

The  position  of  the  large  intestine  being 
constant,  it  is  necessary,  for  sake  of  pre- 
cision, to  speak  of  the  whole  as  to  the 
course  it  takes  in  forming  the  three  divis- 
ions, extending  thus  betw^een  the  small 
intestine  and  anus. 

The  cascum,  or  blind  pouch,  is  the  first 
gut,  which  protrudes  in  the  middle  on  cut- 
ting through  the  abdominal  walls  at  the 
linea  alba.  Its  bend  or  blind  extremity  is 
projecting  into  the  left  hypochondiiac 
region  ;  its  body  crosses  obliquely  the  floor 
of  the  abdomen,  to  reach  the  right  iliac 
region,  where  it  suddenly  bends  at  an  acute 
angle,  being  rather  constricted,  and  forms 
the  colon.  At  this  part  the  latter  receives 
the  ileum,  and  extends  up  the  right  side  of 
the  abdomen  to  the  diaphragm,  where  it 
traverses  the  direction  of  the  spine,  resting  on 
the  ensiform  cartilage  ;  turning  round  the  left 
side,  it  attains  the  left  iliac  fossa  posteriorly, 
where  it  forms  a  twist  like  a  letter  S,  from 
which  similitude  it  has  been  termed  the  Sig- 
moid Flexure  of  the  Colon.  The  gut, 
having  diminished  in  size,  returns  up  the 
same  side  of  the  abdomen  to  the  diaphragm, 
where  it  again  crosses  the  spine.  Being 
now  on  the  right  side,  it  continues  back 
to  a  point  beyond  the  anterior  mesenteric 
artery,  where  it  turns  upward  and  for- 
ward, so  as  to  come  in  front  of  the  artery 
in  question ;  then,  from  right  to  left,  so  as 
to  cross  the  spine  for  the  third  time,  consti- 
tuting the  transverse  colon,  which  is  more 
capacious  than  the  part  preceding  it.  The 
two  curves  which  it  forms,  one  on  the  right 
and  the  other  on  the  left,  are  respectively 
called  the  hepatic  and  gastric  flexures  of 
the  colon.  The  gut  so  proceeds  backward 
along  the  left  side  of  the  mesentery,  being 


diminished  again  in  size,  and  constituting 
the  single  colon,  till  we  get  to  the  posterior 
mesentery  artery,  where,  unaltered  in  other 
respects,  it  takes  a  straight  course  through 
the  pelvis,  out  at  the  anus,  and  hence  the 
name  of  Rectum. 

The  csBum,  so  called  from  having  only 
one  outlet,  being  closed  at  its  anterior  part, 
or  caecum  caput  coli,  from  its  being  the 
blind  head  of  the  colon,  is  vulgarly  termed 
the  water-bag,  owing  to  the  almost  invari- 
able fluidity  of  its  contents. 

It  is  situated,  as  I  have  before  said,  ob- 
liquely along  the  floor  of  the  abdomen,  ex- 
tending backwards  from  left  to  right. 

It  is  attached  to  the  spine  by  a  meso- 
cseum,  which  is  a  fold  of  peritoneum,  com- 
ing off  from  the  spine  on  to  the  superior 
part  of  the  pouch.  There  is  then  the  fold 
already  alluded  to,  which  stretches  from  the 
ileum  on  to  the  csecum,  and,  through  the 
medium  of  the  mesentery,  indirectly  con- 
necting the  latter  with  the  spine. 

The  caecum  is  cone-shaped,  having  an 
apex  and  a  broad  base.  The  former  gene- 
rally protrudes  the  first,  when  a  medium 
longitudinal  incision  is  made  into  the 
abdominal  walls,  although  it  is  situated 
above  the  left  portion  of  the  double  colon, 
whilst  the  liver  is  directly  in  contact  wdth 
the  floor  of  the  abdomen.  Like  the  other 
divisions  of  the  large  intestine,  the  caecum 
is  sacculated.  The  bands  producing  this 
appearance  are  three  in  number  at  the 
apex ;  but  between  two  and  three  inches 
from  this,  one  of  them  bifurcates,  so  that 
four  bands  result,  which  are  continuous  on 
to  the  colon. 

The  colon  arising  from  the  caecum,  re- 
ceives at  first  the  contents  of  the  ileum, 
being  situated  along  and  occupying  the 
greater  part  of  the  floor  of  the  abdomen. 

The  colon  is  generally  distinguished  as 
double  and  single.  By  double,  is  meant 
the  flexures  of  the  gut  from  its  commence- 
ment to  its  gastric  cm-ve ;  whilst  by  the 
single  colon,  is  understood  the  continuation 
of  the  same  intestine  to  the  part  where  the 
rectum  commences. 

The  double  colon  is  attached  by  the  peri- 


THE   HORSE. 


107 


toneum  coming  off  on  to  it  from  the  cae- 
cum, in  the  right  iliac  fossa,  and  continues 
from  the  outer  flexure  on  to  the  inner,  so  as 
to  keep  the  two  in  perfect  apposition.  Thus, 
if  the  abdominal  parietes  are  cut  through, 
the  whole  of  the  double  colon  may  hang 
out,  with  the  exception  of  the  transverse 
portion.  The  latter  is  attached  to  the  right 
kidney,  as  well  as  concave  surface  of  the 
liver,  by  folds  of  peritoneum ;  to  the  spine 
by  the  transverse  meso-colon  ;  and  still 
more  to  the  left,  it  is  loosely  attached  by 
the  gastrocolic  omentum  to  the  stomach 
and  spleen;  besides  which  it  has  a  peri- 
toneal attachment  to  the  left  kidney.  Then 
the  single  colon  commencing,  it  is  loosely 
affixed  to  the  spine  by  an  extensive  peri- 
toneal fold,  the  meso-colon,  similar  to  the 
mesentery,  but  smaller  and  to  its  left :  this 
fold  is  continuous  posteriorly  with  the  meso- 
rectum. 

The  relations  of  the  transverse  colon  are 
important,  no  less  than  interesting,  inas- 
much as  it  is  in  close  connection  with  the 
most  important  abdominal  viscera.  On  the 
right,  its  upper  surface  is  contiguous  to  the 
right  kidney,  as  well  as  to  the  right  and 
Spigelian  lobes  of  the  liver.  In  the  middle, 
its  superior  surface  is  connected  princi- 
pally with  the  pancreas;  and  to  the  left, 
but  still  superiorly,  it  approaches  the  left 
kidney  and  spleen.  Anteriorly,  the  stomach 
also  touches  it,  especially  during  repletion. 

The  shape  of  the  colon  is  very  variable 
in  different  parts  of  its  course.  Thus,  the 
first  portion  of  the  double  colon,  from  the 
right  iliac  fossa  till  it  forms  the  signoid 
flexure,  is  capacious  and  sacculated;  the 
latter  being  due  to  the  four  bands  con- 
tinuous on  to  it  from  the  caecum.  At  the 
signoid  flexure  the  bands  are  completely 
lost,  so  that  the  gut  is  smooth ;  but,  as  we 
extend  up  towards  the  diaphragm,  the  an- 
terior band  begins,  and  then  the  posterior 
one  becomes  apparent;  so  that  the  trans- 
verse and  single  portions  of  the  colon 
are  puckered  by  two  longitudinal  bands. 

The  Rectum,  so  called  from  its  compar- 
ative straight  course  through  the  pelvic 
cavity,  arises  from  the  single  colon,  a  little 


anteriorly  to  the  posterior  mesenteric  artery, 
and  ends  at  the  anus,  where  its  mucus 
membrane  is  continuous  with  the  common 
tegumentary  covering.  It  is  attached  in  its 
anterior  two-thirds  by  a  meso-rectum ;  the 
posterior  third  is  an  exception  to  any  other 
part  of  the  intestinal  track,  in  so  far  as  it 
is  connected  to  adjacent  parts  by  special 
faschisB,  and  at  its  termination  by  certain 
muscles  hereafter  to  be  dwelt  upon. 

The  size  of  the  rectum  is  much  the  same 
as  the  single  colon.  It  is  puckered  in  its 
anterior  part  by  two  longitudinal  bands ; 
and  the  sacculi,  resulting  therefrom,  deter- 
mine the  shape  of  the  faecal  matters. 

The  rectum  is  superiorly  related  to  the 
spine,  whilst  inferiorly  it  comes  in  contact 
with  the  bladder,  bulbous  portions  of  the 
vasa  deferentia,  vesiculse  seminales,  and 
prostate. 

The  structure  of  the  large  intestine  does 
not  vary  essentially  from  that  of  the  small, 
as  it  possesses  the  four  coats,  i.  e.  peritoneal, 
muscular,  cellular,  and  internal  mucus. 

The  peritoneal  tunic  forms  an  entire  cov- 
ering to  the  large  intestine,  with  the  excep- 
tion of  the  superior  sm*face  of  the  trans- 
verse colon  —  which  is  in  contact  with  the 
pancreas  —  and  the  terminating  portion  of 
the  rectum.  The  bands  by  w^hich  it  unites 
the  intestine  to  other  parts  have  been  already 
described.  In  addition  to  the  peritoneum 
forming  an  entire  covering  to  the  gut,  at 
the  attached  margin  of  the  flexures  of  the 
colon  it  constitutes  folds  loaded  with  fat, 
varying  in  width  in  different  parts,  and  clus- 
tered so  as  to  have  deserved  the  name  of 
appendices  epiploicse. 

The  muscular  coat  of  the  large  intestine 
is  differently  developed  in  various  parts. 
Its  fibres  are  of  the  plain  variety,  and  ar- 
ranged in  two  orders.  The  outer  longitud- 
inal set  is  scanty  in  some  parts,  but  in  others 
forms  the  longitudinal  bands  above  aUuded 
to.  These  are  shorter  than  the  actual  length 
of  the  gut  itself,  so  as  effectually  to  pucker 
it.  The  number  of  longitudinal  bands 
varies  from  one  to  four  in  various  parts  of 
the  gut,  and  the  shape  and  breadth  of  the 
latter  is  not  everywhere   the   same.     The 


108 


ANATOMT  AND   PHYSIOLOGY  OP 


longitudinal  fibres  are  abundant  in  the  rec- 
tum, but  they  only  form  bands  in  the  ante- 
rior two-thirds,  as  posteriorly  to  this  they 
uniformly  smTound  the  gut.  The  inner 
layer  of  fibres  encircles  the  whole  of  the 
gut,  being  tliickest  towards  the  apex  of  the 
caecum,  as  well  as  in  the  single  colon  and 
rectum ;  at  the  end  of  the  latter  the  inter- 
nal sphincter-ani  is  formed  by  an  accumu- 
lation of  the  circular  fibres.  The  circular 
fibres  of  the  colon  are  engaged  in  forming 
the  ileo-colic  valve,  hereafter  to  be  described. 

The  cellular  coat  of  the  large  intestine 
resembles  that  of  the  small,  only  not  so 
abundant,  except  at  the  terminating  portion 
of  the  rectum,  where  it  is  much  more  de- 
veloped. 

The  mucus  lining  of  the  large  intestine 
is  continuous  anteriorly  with  that  of  the 
ileum,  posteriorly  with  the  common  integu- 
ment. It  is  thin,  more  or  less  coated  with 
mucus,  scantier  in  glands  than  the  one  of 
the  small  intestine ;  but  the  orifices  of  the 
Lieberkuehnian  crypts  are  more  apparent, 
owing  to  the  surface  here  being  destitute  of 
villi.  Saccular  recesses,  more  or  less  capa- 
cious, exist  in  the  membrane  lining  the 
large  intestine.  The  difference  in  degree 
of  vascularity  gives  rise  to  difference  in  the 
color  of  the  mucus  coat  in  various  portions 
of  the  gut :  thus,  that  lining  the  caecum  is 
generally  more  deeply  colored  than  that  of 
the  colon,  whilst  the  rectal  mucus  mem- 
brane is  more  vascular,  and  hence  redder 
than  the  colic  or  csecal  one. 

At  the  termination  of  the  ileum  is  the 
ileo-colic  or  ileo-caecal  valve,  which  is  con- 
stituted of  two  folds  of  mucus  membrane, 
almost  parallel  to  each  other,  and  horizontal, 
leaving  between  them  an  eliptical  orifice 
when  partially  drawn  asunder.  The  folds 
consist  of  the  circular  fibres  of  the  intes- 
tine, lined  on  the  inner  or  ileac  side  by  the 
villous  membrane  of  the  small,  whilst  on 
the  caecal  and  coUc  side  they  are  covered  by 
the  mucus  membrane  proper  to  the  large 
intestine.  It  is  worthy  of  notice,  that 
though  muscular  fibres  partly  enter  into  the 
construction  of  the  valve,  its  efficiency  is 
explicable  on  purely  mechanical  grounds,  as 


proved  by  the  fact,  that  it  is  competent  in 
the  dead  body. 

The  anus  is  the  outlet  of  the  intestine, 
which  is  perfectly  closed,  except  during  the 
evacuation  of  feculent  matters,  and  is  made 
perceptible  externally  by  the  elevation  of  the 
tail,  being  situated  in  a  space  bounded  su- 
periorly by  the  sacrum  and  coccyx,  laterally 
by  the  ischial  tuberosities,  and  inferiorly  by 
the  urethra  in  the  male  and  vulva  in  the 
female. 

It  is  lined  within  by  the  mucus  mem- 
brane of  the  rectum,  which  is  loose  and  of 
a  marked  red  color.  Its  external  covering 
is  of  common  integument,  destitute  of  hairs. 
Lying  between  the  skin  and  mucus  mem- 
brane are  two  circular  muscles,  whose  office 
is  to  keep  the  anus  closed  and  prevent  con- 
stant evacuation  of  faeces,  whilst  there  are 
other  muscular  appendages  situated  exter- 
nally to  these,  destined  either  to  elevate  or 
retract  the  anus,  being  evidently  antagonis- 
tic to  the  sphincters. 

The  internal  sphincter-ani  is  in  contact 
with  the  attached  surface  of  the  intestinal 
mucus  membrane,  and  separated  from  the 
integument  by  the  external  one.  It  is  con- 
stituted of  the  pale  circular  fibres  of  the  gut, 
but  towards  its  free  edge  certain  colored 
fibres  are  apparent  on  it. 

The  external  sphincter  is  situated  outside 
the  internal  one,  and  within  the  anal  integu- 
ment: it  is  circular,  and  composed  of  red 
fibres,  attached  superiorly  under  the  first 
coccygeal  bone,  and  inferiorly  its  fibres 
blend  in  the  male  subject  in  the  accelerator 
urinee  and  triangularis  penis,  and  in  the 
female  with  the  constrictor  vaginae. 

The  levatores-ani  are  two  pale  muscles, 
attached  on  each  side  of  the  first  coccygeal 
bones,  and,  spreading  downward  and  for- 
ward on  to  the  rectum,  form  an  attachment 
for  the  internal  sphincter,  and  blending  with 
the  longitudinal  fibres,  so  as  to  increase  the 
thickness  of  the  muscular  coat  of  the  rec- 
tum. The  action  of  these  muscles  must 
be  that  of  elevating  the  anus,  and  shorten- 
ing the  rectum  from  before  backward. 

The  retractors  proper  to  the  anus  are  one 
on  each  side  attached  to  the  inner  surface  of 


THE    HORSE. 


109 


the  articular  extremity  of  the  ischium.  Ex- 
tending from  before  backward,  and  rather 
upward,  they  blend  with  the  external 
sphincter.  Their  action  is  obviously  that 
of  retracting  the  anal  opening. 

VESSELS,    NERVES,    AND    LYMPHATICS    OF   THE 
INTESTINE. 

The  intestinal  canal,  as  a  whole,  receives 
arterial  blood  from  the  anterior  and  poste- 
rior mesenteric  arteries,  hepatic  branch  of 
the  coeliac  axis,  with  branches  from  the  in- 
ternal pudic.  The  arteries  of  the  small  in- 
testine are  derived  from  the  anterior  mesen- 
teric, whose  divisions,  varying  from  twenty- 
four  to  twenty-eight,  proceed  to  the  small 
intestine,  with  the  exception  of  four,  which 
minister  to  the  nutrition  and  functions  of 
the  large  intestine.  The  branches  extend- 
ing from  the  main  trunk,  at  acute  angles, 
proceed  between  the  layers  of  the  mesen- 
tery, to  within  one  and  a  half  or  two  inches 
from  the  gut,  where  they  anastomose,  form- 
ing vascular  arches,  from  which  the  second- 
ary branches  arise,  and,  proceeding  on  to  the 
intestine,  ramify  on  the  several  coats,  espe- 
cially the  mucus  one.  The  anterior  division 
of  the  anterior  mesenteric  artery,  proceeding 
to  the  duodenum,  anastomoses  with  the  duo- 
denal branch  of  the  hepatic  artery.  The 
last  iliac  division  inosculates  with  the  csBcal 
and  colic  branches  of  the  same  trunk. 

The  cBBCum  and  colon  receive  arterial 
blood  solely  from  the  branches  derived  from 
the  anterior  mesenteric,  with  a  slight  contri- 
bution from  the  posterior  mesenteric  arteries. 
The  branches  of  the  former  originate  oppo- 
site the  flexure  made  by  the  caecum  and 
colon.  The  cscal  divisions,  two  in  num- 
ber, proceed  downward  and  forward  till 
they  reach  the  gut.  The  posterior  one 
passes  round  the  posterior  part  of  the  bor- 
der of  the  caecum,  to  get  on  the  under  sur- 
face of  the  latter,  extending  to  the  apex,  in 
somewhat  a  straight  course,  and  ramifying 
collaterally ;  at  its  termination  it  forms  a 
vascular  network,  by  anastomosis  with  the 
superior  caecal  artery.  The  latter  one,  reach- 
ing the  gut,  extends  directly  forward  towards 
the  apex,  and  comports  itself  like  the  former. 


Thus  we  see  the  flexure,  formed  by  the 
caecum  and  colon,  is  supplied  by  collateral 
branches,  from  the  superior  and  inferior 
cascal  mesenteric  divisions,  both  these  anas- 
tomosing on  the  corresponding  surfaces  with 
the  colic  arterial  trunks. 

The  two  branches  going  to  the  colon  ex- 
tend, about  parallel  to  each  other,  down- 
wards and  forwards  and  to  the  left,  the  one 
gaining  the  cascal  end  of  the  colon,  whilst 
the  other  proceeds  on  to  the  hepatic  flexure. 
Then  these  may  be  traced,  the  one  back- 
ward and  the  other  forward,  relatively  to 
the  course  of  the  gut,  along  its  superior 
border,  so  as  to  reach  the  sigmoid  flexure, 
where  they  mutually  inosculate.  From  the 
mesenteric  division  going  to  the  transverse 
colon,  is  a  branch  proceeding  on  to  the 
single  portion,  which  anastomoses  poste- 
riorly with  the  posterior  mesenteric.  This 
vessel  divides  first  into  two  branches,  i.  e. 
an  interior  colic  and  a  posterior  rectal  one. 
The  anterior  colic  branch  is  directed  for- 
ward and  downward  between  the  layers 
of  the  meso-colon,  and  divides  into  four  or 
five  branches,  which  bifurcate  and  form 
arches,  like  the  arteries  of  the  small  intes- 
tine, for  the  supply  of  the  contiguous  gut. 
The  arteries  of  the  rectum  are  sometimes 
spoken  of  as  haemorrhoidals,  and  these  are 
distinguished  as  anterior,  middle,  and  pos- 
terior. The  anterior  hasmorrhoidals  are 
formed  by  the  hindermost  branch  of  the 
posterior  mesenteric  artery,  which,  passing 
into  the  folds  of  the  meso-rectum,  supplies 
consecutive  branches  to  the  gut,  till,  poste- 
riorly to  the  peritoneum,  where  the  arteries 
pierce  the  muscular  coat,  and,  forming  a 
network  of  vessels,  anastomose  with  the 
middle  haemorrhoidals,  which  are  the  ramifi- 
cations of  the  internal  pudic*  These  inos- 
culate with  the  posterior  haemorrhoidals 
derived  from  the  same  source.  The  anus 
is  then  supplied  with  blood  from  the  last 
named  branches,  as  well  as  from  perineal 
twigs  of  the  external  pudic. 

The  veins  of  the  intestine  accompany  the 


*  This  artery  sometimes,  erroneously,  goes  by  the  name 
of  its  terminating  branch  —  the  artery  of  the  bulb. 


110 


ANATOMY   AND    PHYSIOLOGY   OF 


arteries,  and  are  equally  distributed.  The 
posterior  mesenteric  vein  is  formed  by  sim- 
ilar divisions  to  those  coming  oft'  from  the 
posterior  mesenteric  artery,  and  then  the 
main  trunk  extends  forwards  and  enters  the 
porta,  near  the  termination  of  the  splenic. 
At  this  spot  the  veins  from  the  small  intes- 
tine, as  well  as  from  the  caecum  and  double 
flexures  of  the  colon,  also  contribute  to 
form  the  large  portal  trunk. 

The  nerves  of  the  intestines  are  derived 
from  the  solar  plexus,  and  they  are  found  in 
association  with  the  arteries.  The  duo- 
denum also  receives  branches  from  the  par 
vagum  nerves,  and  the  rectum  and  anus  are 
supplied  also  by  divisions  of  the  two  last 
sacral  pairs. 

The  lactal  and  lymphatic  vessels  of  the 
intestine  are  anatomically  alike,  and  even 
physiologically  they  admit  of  being  com- 
prehended under  the  same  term,  "lym- 
phatic," because  both  absorb  the  fluid  known 
as  lymph.  But  since  the  lymphatics  of  the 
small  intestine  additionally  contribute  to 
the  function  of  chyliferous  absorption,  they 
have  been  distinguished  as  lacteals,  in  con- 
formity with  the  color  of  the  fluid  which 
they  take  up  during  the  digestive  pro- 
cess. 

The  lacteals  of  the  small,  and  lymphatics 
of  the  large  intestine,  enter  a  set  of  lym- 
phatic glands,  by  no  means  numerous,  and 
of  small  size,  situated  along  the  attached 
border  of  the  gut.  From  these  the  lacteals 
ascend  to  about  twenty-five  or  thirty  lym- 
phatic glands  of  larger  size  than  the  others, 
situated  at  a  short  distance  from  the  spine, 
between  the  folds  of  the  mesentery,  from 
which  the  lymph  is  then  conducted  into  the 
receptaculum  chyli.  From  the  large  intes- 
tine the  lymphatics  enter,  in  addition  to  the 
intestinal  set  of  glands,  others  situated  in 
the  lumbar  region,  partly  between  the  folds 
of  the  meso-colon  and  meso-rectum,  from 
which  the  lymph  is  carried  into  the  common 
reservoir. 

The  receptaculum  chyli  receives  the  fluid 
from  the  lymphatic  vessels  of  all  the  ab- 
dominal viscera,  as  well  as  from  other  parts. 
It    is    a    membranous    pouch   of  various 


calibre,  lying  in  contact  with  the  right  crus 
of  the  diaphragm,  and  right  psoas  muscle, 
corresponding  in  situation  to  the  second  and 
third  lumbar  vertebra;.  It  gradually  con- 
stricts anteriorly,  and  crossing  the  aorta  to 
get  on  its  left  side,  enters  the  thorax,  and 
here  becomes  known  as  the  thoracic  duct, 
which  empties  itself  into  the  right  axillary 
vein. 

SPLEEN. 

The  spleen,  although,  possibly,  not  bear- 
ing any  physiological  connection  with  the 
digestive  process,  still,  from  its  anatomical 
relations,  conveniently  admits  of  description 
here.  It  is  a  singularly  elastic  organ,  of  a 
purplish  grey  color;  smooth  on  its  outer 
surface,  and  composed  of  a  spongy  texture, 
enclosed  in  fi.brous  tissue.  The  color  of 
the  spleen  is  generally  darker  in  herbivora 
than  in  carnivorous  quadrupeds,  as  in  the 
latter  it  is  more  of  a  red  color. 

It  is  situated  in  the  left  hypochondrium, 
and  partly  in  the  epigastrium,  being  at- 
tached by  its  outer  tunic  to  the  stomach, 
left  kidney,  and  transverse  colon. 

It  is  scythe-shaped,  being  small  and 
pointed  anteriorly,  but  broad  posteriorly. 
It  is  smooth,  and  somewhat  convex  on  its 
inferior  surface,  whilst  its  superior  one  is 
divided  into  two  unequal  halves,  by  a  fissure 
termed  the  hilum.  The  anterior  division 
is  narrow,  but  the  posterior  one  is  broad 
and  triangular  in  shape.  The  margin  of 
the  spleen  is  sharp  all  round.  The  size  of 
the  organ  varies  considerably  in  different 
subjects,  and,  according  to  circumstances, 
in  the  same  animal. 

The  spleen  is  related,  by  its  superior 
surface,  to  the  left  end  of  the  greater  curva- 
ture of  the  stomach,  and  to  the  diaphragm ; 
at  its  broad  base  it  is  in  close  relation  with 
the  left  kidney ;  its  inferior  surface  is  con- 
nected with  both  double  and  single  portions 
of  the  colon. 

The  spleen  has  two  coats,  a  parenchyma, 
blood  vessels,  nerves,  and  lymphatics,  need- 
ing separate  description. 

The  external  coat  is  peritoneum,  which 
forms  not  only  a  covering  to  the  organ  itself, 


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t 


EXPLANATION   OF   FIGURE  XII. 


MUSCULAR  STRUCTURE. 

FORWAKD  PARTS. 

*.  Ligamentum  colli. 

a".  Trapezius. 

b\  Rhomboideus  longus. 

c".  Scalenus. 

g".  Postea  spinatus. 

h'.  Teres  major. 

i".  Latissimus  dorsi. 

I".  Scapulo  ulnaris. 

m".  n".  Triceps  extensor  brachii. 

p".  Flexor  metacarpi  externus. 

5".  Flexor  metacarpi  medius. 

r.  Flexor  metacarpi  internus. 

S  ".  Extensor  metacarpi  magnus. 

S.  Splenius. 

u.  Levator  humeri. 

a;".  Extensor  pedis. 

c".  Obliquus  externus  abdominis. 

POSTERIOR  PARTS. 

h'.  i'.  Gluteal  muscles. 

/.    Triceps. 

Jc.     Biceps  abductor  tibialis,  posterior. 

V.    Adductor  tibialis  internus. 

m.   Tensor  vagina. 

n.    Region  of  the  vastus  internus. 

r.     Gastrocnemius  internus. 

i.  S.  Gastrocnemius  externus  and  internus. 

a:.    Extensor  metatarsi. 

y.     Peroneus. 

i'.     Flexor  pedis  accessorius. 

e'.  g'\    Coccygeal  muscles. 

4.  Subcutaneous  thoracic  vein. 

5.  Saphena  vein, 

6.  Radial  vein. 

OSSEOUS  STRUCTURE. 

10.  20.  21.    The  pelvis, 
lU    Cervical  veitebroe. 

15.  Coccygeal  bones. 

16.  The  true  ribs. 

17.  The  false  ribiS. 

18.  Sternum. 

22.  Femur. 

23.  Patella. 

33.  Scapula. 

34.  Humerus. 

35.  Radius. 

d.    Dorsal  spines. 
f.    Ulnwr. 


THE   HORSE. 


Ill 


but  bonds  of  connection  between  it  and 
other  parts,  such  as  the  gastro-splenic  omen- 
tum, and  the  attachment  to  the  kidney  and 
transverse  colon  heretofore  described.  This 
coat  is  smooth  externally,  rather  closely 
attached  to  the  fibrous  coat  internally,  but 
of  considerable  elasticity,  so  as  to  allow  the 
spleen  sufficient  freedom  for  distention. 

The  second  or  fibrous  coat,  also  termed 
the  albugineous  or  elastic  coat,  is  that  closely 
applied  to  the  parenchyma  of  the  organ. 
It  consists  of  yellow  and  white  fibres,  aiid 
in  some  parts,  such  as  in  the  trabeculas, 
Koelliker  has  found  plain  muscular  fibres, 
which  he  says  do  not  exist  in  the  external 
portion  of  the  fibrous  tunic  in  the  horse. 
The  covering  not  only  envelopes  the  outer 
surface  of  the  organ,  but  sends  sheaths  and 
processes  into  its  substance.  The  sheaths 
are  purposed  for  covering  vessels,  whilst 
the  processes,  termed  also  trabeculsB,  divide 
the  substance  of  the  spleen  into  areolae  or 
interspaces,  which  contain  a  red  matter, 
easily  washed  and  pressed  out,  known  as 
the  splenic  pulp.  The  trabecular  also  arise 
as  processes  from  the  vascular  sheaths,  as 
well  as  from  the  external  tunic.  When  the 
pulp  has  been  thoroughly  washed,  the  outer 
coat,  with  the  trabeculse  and  sheaths,  have 
the  appearance  of  a  framework  or  skeleton. 

The  splenic  pulp  has  a  medullary  aspect, 
being  composed  of  cells  and  blood  vessels ; 
and  if  the  organ  be  cut  clean  in  any  direc- 
tion, ^^^e  see,  besides  the  cut  ends  of  vessels 
and  trabeculsB,  certain  pearlish  looking 
bodies,  named,  from  their  discoverer,  Malpig- 
hian  Corpuscles.  If  divided,  fluid  escapes 
from  the  cavity  which  exists  in  their  in- 
terior. They  are  perfectly  visible  to  the 
naked  eye,  being  about  one-thirtieth  of  an 
inch  in  diameter  ;  and,  with  a  pocket  glass, 
they  may  be  seen  attached  to  the  small  ar- 
terial trunks,  if  the  pulp  has  been  previously 
carefully  washed. 

The  spleen  derives  its  arterial  blood 
through  the  splenic  artery,  which  is  the  main 
division  of  the  coeliac  axis.  Winding  be- 
tween the  folds  of  the  gastro-splenic  omen- 
tum, it  not  only  sends  numerous  branches 
through  the  hilum,  and  on  to  the  surface  of 


the  spleen,  but  also  supplies  the  stomach, 
largely  inosculating  with  the  gastric  artery, 
so  that  the  two  might  mutually  perform 
each  other's  office,  if  the  main  trunk  of 
either  w*ere  obstructed. 

The  splenic  vein  is  similarly  distributed 
to  the  artery,  and  it  empties  its  blood  into 
the  vena  porta,  just  anteriorly  to  the  pos- 
terior mesenteric  vein. 

The  nerves  of  the  spleen  are  derived  from 
the  solar  plexus,  and  with  the  splenic  artery 
enter  the  spleen. 

The  lymphatics  of  the  spleen  are  said  by 
Koelliker  to  be  scanty;  but  Dr.  Sharpey 
tends  rather  to  the  belief  that  they  are 
abundant.  They  are  arranged  superficially 
and  deep,  both  sets  anastomising  freely 
with  each  other,  and,  reaching  the  hilum, 
they  enter  various  scattered  lymphatic 
glands  in  the  peritoneal  folds,  and  then 
empty  into  the  receptaculum  chyli. 

LIVER. 

The  liver  is  the  largest  gland  in  the  body, 
and  proportionately  largest  during  certain 
periods  of  foetal  life.  It  is  of  a  dark  reddish 
brown  color,  and  destined  for  the  office  of 
biliary  secretion. 

It  is  situated  across  the  long  axis  of  the 
body,  in  the  right  hypochondriac,  epigastric, 
and  partly  in  the  left  hypochondriac  regions. 

It  is  attached  to  various  parts  by  five 
ligaments,  four  of  which  are  peritoneal 
folds,  and  one  is  the  remnant  cord  resulting 
from  the  obliteration  of  the  unbilical  vein 
within  the  abdomen.  These  attachments 
will  be  more  fully  described  with  the  peri- 
toneal tunic. 

The  external  aspect  of  the  liver  is  smooth, 
being  convex  superiorly  and  concave  inferior- 
ly,  broad  posteriorly,  and  sharp  anteriorly. 
It  .has  a  granular  appearance,  and  a  very 
superficial  inspection  clearly  shows  that  it  is 
composed  of  lobules,  about  the  size  of  a 
pin's  head. 

The  hepatic  substance  is  irregularly 
divided  into  numerous  segments  by  fissures, 
which  either  extend  through  the  gland  from 
side  to  side,  or  are  mere  grooves  of  more 
or  less  depth.     The  different  segments  of 


112 


ANATOMY   AND   PHYSIOLOGY   OF 


the  gland  or  lobes  are  three  principal  ones 
—  right,  middle,  and  left — to  which  smaller 
ones  are  appended. 

The  right  lobe  is  the  largest  of  the  three, 
situated  in  the  right  hypochondrium,  being 
thickest  posteriorly  and  sharp  anteriorly. 
The  supero-posterior  part  of  the  right  lobe 
is  marked  by  a  depression,  for  the  adapta- 
tion of  the  anterior  part  of  the  right  kidney. 
At  the  superior  part  of  the  right  lobe  is  an 
excavation  for  the  vena  cava,  which  extends 
from  behind  forward,  and  marks  off"  the 
division  bet\,veen  the  right  and  middle  lobe. 
The  vena  cava  is  here  more  or  less  imbed- 
ded in  the  substance  of  the  right  lobe,  but, 
generally  speaking,  it  is  superficial  in  the 
horse,  and  only  an  imperfect  channel  is 
formed  for  it. 

Projecting  from  the  inferior  surface  and 
posterior  part  of  the  right  lobe,  is  the  lobulus 
spigelii,  which  is  of  considerable  size,  being 
broad  posteriorly,  and  attached  by  its 
superior  and  left  border,  so  that  it  projects 
anteriorly  and  narrows ;  its  apex  gradually 
tapers,  and  has  been  capriciously  designated, 
by  the  lovers  of  a  quintuple  hepatic  arrange- 
ment, lobulus  caudatus. 

The  middle  lobe  of  the  liver  is  the  smal- 
lest of  the  three;  it  is  crossed  on  its  inferior 
surface  by  the  transverse  fissure  or  porta  of 
the  fiver,  at  which  the  vessels  and  ducts 
enter  into  and  issue  from  the  gland.  The 
middle  lobe  in  the  horse  is  divided  at  its 
anterior  part  into  five  or  six  portions,  and 
Mr.  Percivall,  in  his  Anatomy  of  the  Horse, 
at  page  259,  has  termed  it  the  lobulus 
scissatus.  It  is  traversed  antero-posteriorly 
by  a  channel  for  the  remnant  of  the  um- 
bilical vein,W'hich  eventually  joins  the  vena 
porta. 

The  left  lobe  is  the  thinnest  of  the  three, 
but  occupies  an  intermediate  position  in 
length  and  breadth.  It  is  very  thin  at  its 
left  margin,  and  gradually  thickens  pos- 
teriorly. At  its  posterior  and  left  side  is 
a  depression,  in  which  the  oesophagus  rests. 
Sometimes  the  left  lobe  is  divided  into  two 
at  its  anterior  part ;  at  others  it  is  single. 

The  superior  surface  of  the  liver  is  convex, 
and  in  contact  with  the  pillars  and  expanded 


portion  of  the  diaphragm.  The  right  as 
well  as  the  Spigelian  lobes,  are  in  relation 
posteriorly  with  the  right  kidney  and  right 
supra-renal  capsule,  infcriorly  with  the  head 
of  the  pancreas,  duodenum,  and  transverse 
colon.  The  middle  lobe  is  related  inferiorly 
to  the  pancreas,  but  partially  separated  from 
it  by  the  vena  portae.  It  also  suspends  the 
duodenum,  and  its  left  edge  is  loose  and  in 
close  proximity  to  the  flexures  of  the  colon. 
The  left  lobe  is  related  posteriorly  to  the 
CESophagus,  and  inferiorly  to  the  left  end  of 
the  stomach.  The  pancreas  also  stretches 
across  its  posterior  part,  partially  separating 
it  from  the  transverse  colon. 

The  liver  receives  an  incomplete  covering 
of  peritoneum.  The  latter,  reflected  from 
the  diaphragm  on  to  the  concave  surface  of 
the  middle  lobe  of  the  liver,  forms  a  double 
membranous  layer,  known,  in  accordance 
with  its  shape,  as  the  falsiform  ligament, 
and  holding  in  its  free  and  concave  margin 
the  round  ligament,  the  representative  of  a 
foetal  structure,  the  umbilical  vein.  Fur- 
thermore, the  fiver  is  provided  with  a  coro- 
nary ligament,  that  surrounds  the  foramen 
dextrum  of  the  diaphragm,  through  which 
the  vena  cava  passes.  The  lateral  ligaments 
are  distinguished  as  right  and  left ;  they 
connect  each  lateral  lobe  to  the  diaplu-agm. 

The  only  connections  of  the  liver  that 
remain  to  be  mentioned  are  the  stomach, 
duodenum,  transverse  colon,  and  pancreas 
to  its  inferior  surface,  and  the  right  kid- 
ney to  the  posterior  part  of  the  right  lobe. 

Dissecting  off  the  serous  tunic,  it  is  found 
connected  with  the  biliary  surface  by  cel- 
lular tissue,  continuous  at  the  porta  with  the 
so-called  capsule  of  Glisson.  The  latter 
extends  into  the  liver  as  a  common  sheath 
to  blood  vessels,  nerves,  lymphatics,  and 
biliary  ducts. 

To  proceed  with  further  description  of 
the  liver  would  be  useless,  unless  first  ex- 
amining the  blood  vessels  and  ducts  in  that 
part  of  their  course  which  is  external  to  the 
organ.  The  hepatic  artery  is  quite  subor- 
dinate in  size,  considering  the  magnitude 
of  the  organ  and  amount  of  its  secretion. 
It  is  a  branch  of  the  ccefiac  axis,  at  first  in 


THE  HORSE. 


113 


contact  with  the  pancreas,  and  then  be- 
tween the  folds  of  the  gastro-hepatic  omen- 
tum, and  it  reaches  the  porta  on  the  left 
side  of  the  portal  vein.  After  giving  off 
pancreatic  and  duodenal  branches,  it  di- 
vides into  two,  a  right  and  a  left  one.  The 
right,  the  largest  and  somewhat  the  longest, 
penetrates  into  the  right  lobe,  giving  off 
collateral  branches,  first  to  the  middle  and 
then  to  the  right  lobe  itself.  The  left  is  the 
smallest  division,  and  is  distributed  to  the 
lobe  corresponding  to  it  in  position,  and  also 
to  the  middle  one. 

The  liver  is  exceptional  for  having,  be- 
sides an  artery,  another  afferent  vessel  —  a 
vein,  known  as  the  portal  vein,  formed  by 
the  splenic,  which  also  receives  the  gasti'ic 
and  mesenteries,  meeting  each  other  at  the 
same  spot  near  the  posterior  part  of  the 
pancreas.  From  its  origin,  the  portal  vein 
takes  an  oblique  course  from  left  to  right 
through  the  pancreas,  and  being  surrounded 
by  nerves,  it  reaches  the  porta  of  the  liver, 
and  here  divides  into  three  principal 
branches,  one  for  each  lobe. 

At  the  porta  we  also  see  the  biliary  duct 
coming  out,  formed  by  the  union  of  several 
branches,  corresponding  in  number  to  the 
ramification  of  the  blood-vessels.  This 
duct  passes  through  the  gastro-hepatic 
omentum,  meeting  the  pancreatic  duct  at 
almost  a  right  angle,  and  with  it  opening 
into  the  duodenum  about  five  or  six  inches 
from  the  pylorus. 

Having  thus  far  considered  the  main 
vessels,  we  may  examine  further  the  inter- 
nal structure  of  the  liver.  At  the  porta 
the  branches  of  the  vessels  and  ducts  are 
associated  together,  and  surrounded  by  cel- 
lular tissue,  which  sheaths  grooves  or  canals, 
cut  in  various  directions  in  the  substance  of 
the  organ.  These  are  the  portal  canals, 
and  the  cellular  tissue  in  question  is  Glis- 
son's  capsule. 

The  vessels  and  ducts  ramifying  on  the 
sheath  acquire  the  name  of  vaginal  branches, 
and,  as  they  are  traced  between  the  lobules, 
they  are  termed  interlobular.  Here  the  un- 
assisted eye  ceases  to  take  cognizance  of 
their  further  relation  ;  but,  with  careful  dis- 

15 


section,  and  a  common  pocket  lens,  they 
may  be  traced  to  the  lobules,  which  they 
enter;  and  the  blood  of  the  hepatic  artery 
and  portal  vein  is  emptied  into  a  common 
set  of  vessels,  the  hepatic  vein.  The  rela- 
tion of  these  vessels  in  the  lobules  may  be 
seen  on  the  surface  in  a  good  injected  speci- 
men of  liver,  where  the  hepatic  veins  have 
been  injected  one  color,  and  the  other  ves- 
sels differently.  By  this  means  the  centre 
of  the  lobule  is  colored  with  the  injection 
thrown  into  the  hepatic  veins,  and  the  cir- 
cumference with  that  of  tl^e  portal  vein. 

The  hepatic  veins  issuing  from  the  lo- 
bules cross  the  structure  of  the  liver  in  sep- 
arate grooves,  formed  by  the  coalescence  of 
the  hepatic  particles,  so  that  their  base  is  in 
contact  with  the  veins,  and  hence  the  name 
of  the  latter  is  that  of  the  sub-lobular  he- 
patic veins.  These  empty  into  the  posterior 
cava  by  several  orifices,  as  well  as  by  two 
larger  ones,  guarded  by  semi-lunar  valves, 
situated  just  at  the  foramen  dextrum  of  the 
diaphragm. 

In  addition  to  the  blood-vessels  and  ducts 
of  the  liver,  it  is  supplied  with  nerves  from 
the  solar  plexus,  which  ramify  with  the  ves- 
sels. 

The  lymphatics  of  the  liver  are  abundant, 
and  aiTanged,  like  in  other  organs,  as  a  su- 
perficial and  deep  set,  which  inosculate 
freely  in  the  substance  of  the  organ,  and, 
uniting  to  form  several  branches,  they  issue 
from  the  porta  of  the  liver,  passing  through 
some  lymphatic  glands  situated  round  the 
fissure,  and  from  this  they  advance  to  the 
receptaculum  chyli. 


PANCREAS. 


The  pancreas  is  a  compound  vesicular  or 
racemose  gland,  being  much  of  the  same 
nature  as  the  salivary  glands. 

The  pancreas  occupies  the  interval  be- 
tween the  layers  of  the  transverse  meso- 
colon, along  the  upper  surface  of  the  trans- 
verse colon. 

Its  attachments  are  merely  cellular,  with 
the  exception  of  the  pancreatic  duct,  which 
attaches  it  pretty  closely  to  the  duodenum. 

The  pancreas  is  spoken  of  as  having  a 


114 


ANATOMY   AND   PHYSIOLOGY   OP 


body,  a  head,  and  a  tail.  The  body  of  the 
pancreas  is  that  part  stretched  across  the 
middle  lobe,  whUc  the  head  is  longitudinally 
extended,  being  almost  parallel  to  the  vena 
portaB,  and  situated  below  and  to  the  right 
of  that  vessel.  The  head  is  broad  ante- 
riorly and  rather  narrow  posteriorly,  and 
continuous  from  below  upward,  and  from 
right  to  left,  then  from  behind  forward, 
to  gain  attachment  to  the  body,  so  as  to 
form  a  ring  for  the  passage  of  the  vena 
portae.  The  part  to  the  left  of  this  vein  is 
termed  the  tail  of  the  pancreas. 

The  pancreas  is  related  by  its  superior 
surface  to  the  right,  left,  and  Spigelian 
lobes  of  the  liver,  also  to  the  vena  cava  and 
aorta,  which  separate  it  from  the  phrenic 
crura.  The  posterior  part  of  the  head  of 
the  pancreas  is  in  relation  with  the  right 
supra-renal  body.  The  tail  of  the  pancreas 
is  stretched  transversely  to  the  branches  of 
the  coeiac  axis,  and  attached  to  the  left 
kidney  by  loose  cellular  tissue.  The  in- 
ferior surface  is  in  contact  with  the  trans- 
verse colon. 

On  examining  carefully  the  structure  of 
the  gland,  it  is  found  to  consist  of  clusters 
of  cells,  from  which  ducts  arise,  and  these 
unite  to  form  a  main  trunk,  that  is  trace- 
able back  to  the  tail  of  the  pancreas,  in- 
creasing in  size  till  it  reaches  the  anterior 
extremity  of  the  head,  where  it  pierces  the 
duodenum  together  with  the  hepatic  duct. 
Besides  these  clusters  of  cells  and  ducts, 
the  gland  contains  connecting  cellular 
tissue. 

The  pancreas  is  supplied  with  arterial 
blood  by  branches  from  the  three  divisions 
of  the  ccelic  axis,  as  well  as  from  the  an- 
terior mesenteric. 

The  pancreatic  veins  empty  themselves 
into  the  splenic. 

The  nerves  are  derived  from  the  solar 
plexus,  and  the  lymphatics  of  the  pancreas, 
on  issuing  from  the  glandular  substance, 
may  be  traced  to  the  common  reservoir  of 
chyle  and  lymph. 

GENITO    URINARY    APPARATUS. 

Having  already  described  the  intra-abdo- 


minal portion  of  the  alimentary  canal,  and 
its  accessories,  I  proceed  to  the  considera- 
tion of  that  portion  of  the  genito-urinary 
apparatus  as  contained  within  the  abdomen, 
in  the  widest  acceptation  of  the  latter 
term.  By  this  I  mean  the  kidneys,  and 
with  them,  for  anatomical  convenience,  I 
classify  the  supra-renal  capsules,  then  the 
ureters,  bladder,  membranous  portion  of 
the  urethra,  vasa  deferentia,  vesiculae  semi- 
nales,  prostate  and  Cowper's  glands,  with 
which  I  shall  conclude. 

KIDNEYS. 

The  kidneys  are  a  pair  of  glands,  whose 
function  it  is  to  secrete  urine.  They  are 
distinguished  as  right  and  left,  being  both 
situated  in  the  lumbar  region  ;  but,  so  far 
as  concerns  their  topographical  anatomy, 
notwithstanding  their  similarity  in  position, 
they  need  separate  notice. 

The  right  kidney  is  more  anteriorly  situ- 
ated than  the  left,  coming  in  contact  with 
the  posterior  part  of  the  right  lobe  of  the 
liver,  to  which  it  is  attached.  It  is  also 
fixed  to  the  abdominal  parietes  by  peri- 
toneum, and  to  the  spine  by  blood-vessels. 

Its  shape  is  that  of  a  bent  ovoid,  being 
more  symmetrical  than  the  left.  It  has  two 
surfaces    and   two  borders. 

Though  differing  in  these  marked  general 
characters,  the  kidneys  resemble  each  other 
in  several  equally  obvious  points  of  their 
general  anatomy.  Both  kidneys  have  a 
peritoneal  and  an  albugineous  coat,  both 
have  an  excretory  duct,  vessels  and  nerves, 
with  a  structure  also  equal  in  the  two,  con- 
stituting the  bulk  of  the  organ.  Exter- 
nally to  the  peritoneal  tunic  is  a  more  or 
less  thick  stratum  of  fat,  which  is  more 
abundant  in  old  than  in  young  animals, 
when  in  a  state  of  obesity. 

The  peritoneal  covering  of  the  kidneys 
is  incomplete,  especially  that  of  the  right 
one,  whose  inferior  surface  and  convex 
border  are  the  only  parts  coated  by  it.  The 
left  kidney  is  also  covered  on  its  superior 
surface  to  a  considerable  extent,  sometimes 
more  and  sometimes  less.  The  attachments 
which   each  organ  contracts    through   the 


THE   HORSE. 


115 


medium  of  this  serous  investment  have  al- 
ready been  described. 

The  albugineous  tunic  is  fibrous,  and 
partly  sub-serous.  It  forms  a  distinct  cap- 
sule, attached  to  the  substance  of  the  organ 
by  fibrous  prolongations,  which  are  in  some 
parts  arranged  in  pits  and  depressions,  so 
as  to  mark  out  divisions  on  the  surface  of 
the  kidney.  In  addition  to  this,  the  albu- 
sfineous  coat  surrounds  the  vessels  and 
ureter  at  the  hilus,  and  enters  the  substance 
of  the  organ. 

On  cutting  the  kidney  horizontally  from 
the  convex  to  the  concave  border,  there  are 
three  different  parts  brought  into  view,  to 
be  taken  into  consideration.  Firstly,  a 
dark  conteur,  of  about  half  an  inch  or  more 
in  thickness,  being  generally  less  at  the  ex- 
treme ends  of  the  Iddney  than  at  its  middle, 
which  completely  encircles  the  central  part 
of  the  gland,  and  is  termed  the  cortical 
sti'ucture,  from  its  being  most  external. 
This  part  of  the  kidney  has  somewhat  a 
granular  aspect,  and,  when  the  vessels  are 
full  of  blood  or  injection,  they  appear  more 
or  less  arborescent,  and  clustered  at  innu- 
merable minute  but  visible  spots,  to  form 
the  Malpighian  tufts.  Next  to  this  is  a 
lighter  colored  material,  rather  ash-colored, 
but  having  a  reddish  hue,  termed  the  me- 
dullary substance.  This  term  is  not  given 
to  it  from  the  fact  that  it  is  medullary  in 
consistence,  but  used  in  the  metaphorical 
sense  of  being  internally  or  centrally  situ- 
ated. 

Approaching  still  nearer  to  the  concave 
border  of  the  kidney,  is  a  funnel-shaped 
cavity,  with  its  apex  towards  the  hilus,  and 
the  base  bounded  by  the  medullary  sub- 
stance, which  is  the  pelvis.  The  apex  is 
tubular,  and  continuous  with  the  ureter, 
of  which  the  cavity  is  but  an  expansion. 

The  walls  of  the  cavity  are  lined  by  a 
mucus  membrane,  which  is  loosely  applied 
to  the  medullary  substance,  and  thrown 
into  folds,  taking  a  radiated  direction  from 
the  mouth  of  the  ureter.  Opposite  the 
apex  of  the  pelvis,  the  membrane  is  adher- 
ent to  a  prominent  border  of  the  medullary 
substance,  concave  from  before  backward, 


but  convex  from  above  downward,  and  is 
pierced  by  foramina,  into  which  the  lining 
membrane  of  the  pelvis  extends,  so  as  to 
form  the  uriniferous  tubes.  On  dissecting 
carefully  away  the  mucus  membranes  of 
the  pelvis,  we  reach  to  the  fibrous  tunic, 
which  is  not  continuous  on  the  medullary 
ridge,  but  merely  attached  to  its  sides,  so 
as  to  increase  the  length  of  the  boundaries 
of  the  cavity. 

The  ureter  arising  from  this  dilatation  is 
continuous  outward  toward  the  spine,^and 
then  backward,  being  related  superiorly, 
as  it  issues  from  the  hillus,  with  the  renal 
vein  ;  and  then  crossing  the  posterior  part 
of  the  kidney  at  its  inferior  surface,  it  gets 
betw^een  the  peritoneum  and  psoas  muscles, 
and  is  then  traceable  back  to  the  bladder, 
into  which  it  opens. 

The  renal  arteries,  one  for  each  Iddney, 
arise  at  almost  right  angles  from  the  aorta, 
after  the  latter  has  given  off  the  anterior 
mesenteric.  The  right  one  is  more  ante- 
riorly situated,  and  is  longer  than  the  left 
one.  After  each  renal  artery  has  given  off 
a  branch  or  more  to  the  supra-renal  cap- 
sule of  the  same  side,  it  divides,  on  reach- 
ing the  hilus,  into  a  variable  number  of 
branches,  usually  eight  or  ten,  which  pierce 
the  kidney  at  different  parts  of  the  hilus, 
whilst  a  few  branches  proceed  along  the 
surface,  supplying  the  capsule,  and  then 
also  piercing  the  organ.  The  arterial 
branches  entering  the  kidney  have  a  de- 
finite arrangement,  forming  a  kind  of  arch 
superiorly  to  the  pelvis,  from  which  second- 
ary divisions  emanate  and  pierce  the  organ 
in  all  directions,  so  as  to  reach  the  cortical 
substance,  abruptly  dividing  into  numer- 
ous branches,  which  eventually  subdivide 
to  form  capillaries.  By  this  it  is  evident 
that  the  cortical  substance  is  more  vas- 
cular than  the  medullary ;  indeed  the  latter 
is  very  scantily  supplied  with  arterial 
blood. 

From  the  arterial  terminations  the  venous 
origins  occm-,  and  these  unite  to  form 
branches,  having  a  similar  arrangement  as 
the  arteries ;  only  as  they  reach  the  pelvis, 
almost   opposite   the   apex,   they   meet   to 


116 


ANATOMY    AND    PHYSIOLOGY    OF 


form  a  wide,  capacious  tiamk,  the  renal 
vein.  This  is  supplied  with  valves,  not  all 
of  which  are  perfect.  At  the  opening  of 
each  renal  vein  into  the  cava  is  a  semi- 
lunar flap,  overlapping  the  posterior  part. 

The  nerves  of  kidneys  are  numerous, 
and  derived  from  the  renal  plexuses  of  the 
sympathetic ;  they  accompany  the  vessels 
with  which  they  penetrate  thek  respective 
organs. 

Lymphatics  may  be  seen  issuing  from 
the  hillus  of  the  kidney ;  they  enter  some 
lymphatic  glands  there  situate,  and  then 
convey  the  lymph  into  the  receptaculum 
chyli. 

SUPRA    RENAL    CAPSULES. 

These  bodies,  also  called  capsulsB  supra- 
renales,  seu  atrabilariae,  are  two  in  num- 
ber, and  belong  to  the  class  vascular 
glands,  whose  office  is  very  indefinitely 
known. 

They  are  situated  one  on  each  side  of 
the  spine,  across  the  duection  of  the  renal 
vessels.  Their  attachments  are  effected  by 
vessels,  as  well  as  by  the  peritoneum,  on 
their  inferior  sm-face,  connecting  them  to 
the  corresponding  kidney  and  around  to  the 
spine. 

The  shape  of  the  supra-renal  bodies  is 
much  the  same  on  either  side,  being  that 
of  a  slightly  bent  ellipsis.  They  vary 
from  three  to  four  inches  in  length,  and 
from  one  and  a  half  to  two  inches  in 
breadth. 

Their  concave  border  corresponds  to  the 
renal  vessels,  as  well  as  to  the  anterior 
mesenteric  arteries.  The  convex  border  is 
in  contact  with  the  inner  margin  of  the 
Iddney.  The  anterior  extremity  of  the 
right  one  is  in  connection  with  the  right 
hepatic  lobe,  whUst  its  inferior  surface  is 
in  connection  with  the  commencement  of 
the  colon.  The  left  supra-renal  capsule  is 
related  anteriorly  to  the  pancreas,  and  infe- 
riorly  to  the  transverse  colon. 

The  peritoneal  coat  of  the  supra-renal 
capsules  is  merely  confined  to  their  inferior 
surface.  The  proper  substance  of  the 
organ  is  enclosed  in  a  fibrous  or  albugine- 


ous  coat,  which  forms  a  distinct  covering 
externally,  and  becomes  continuous  as 
sheaths  to  vessels  internally. 

On  cutting  horizontally  across  a  supra- 
renal capsule,  it  is  found  to  consist  of  an 
outer  cortical  and  an  internal  medullary 
substance.  The  cortical  substance  is  a 
brownish  yellow,  due  to  fat  contained  in 
vesicles,  which,  according  to  Professor  Hein- 
rich  Frey,  are  smaller  toward  the  surface 
than  more  internally.  The  meduUary  sub- 
stance has  a  greyish  aspect,  and  vessels  are 
apparent  in  it,  as  also  a  yellow  tinge,  due, 
according  to  the  above-named  author,  to 
similar  vesicles,  as  in  the  cortical  substance, 
only  much  scantier  in  fat. 

The  arteries  of  the  supra-renal  capsules 
are  offsets  of  the  renals  and  anterior  mesen- 
teric, as  well  as  of  the  aorta,  but  very 
variable  in  number  and  origin.  They  are, 
however,  always  abundant,  and  enter  the 
organ  principally  at  its  concave  border. 

The  veins  are  larger  than  the  arteries,  and 
pour  their  contents  on  the  left  into  the  renal 
vein,  and  into  the  vena  cava  on  the  right. 

The  nerves  of  the '  supra-renal  capsules 
are  very  abundant,  and  derived  from  the 
renal  plexus.  Professor  Frey  states,  that 
in  the  horse,  gangloin  corpuscles  constitute 
one  of  the  structural  elements  of  the  nervous 
tissue  in  this  situation. 

URETERS. 

The  ureters,  one  to  each  kidney,  are  con- 
duits between  the  kidneys  and  the  bladder, 
for  the  passage  of  urine.  Their  caliber  is 
various,  being  about  one-third  of  an  inch 
broad,  but  getting  narrower  posteriorly. 

As  the  ureters  issue  from  the  kidneys, 
they  converge  towards  the  spine;  then  pro- 
ceed suddenly  backward,  till  they  reach  the 
brim  of  the  pelvis,  having  thus  greatly 
diverged ;  here  they  converge  again,  passing 
downward  and  backward  to  reach  the  sides 
of  the  body  of  the  bladder,  which  they 
pierce. 

In  their  course,  the  ureters  are  attached  to 
the  kidney  and  psoas  parvus  by  loose  cellu- 
lar tissue,  and  by  the  peritoneum,  which 
suspends  them,  by  being  stretched  across 


THE   HOESE. 


117 


their  inferior  surface.  After  the  ureters  have 
crossed  the  spermatic  and  iliac  vessels,  they 
are  received  within  a  fold  of  peritoneum, 
constituting  the  false  ligaments  of  the 
bladder. 

They  pierce  the  muscular  coat  of  the 
bladder  at  a  distance  of  about  three  inches 
from  each  other,  if  the  viscus  be  distended. 
They  pass  between  the  muscular  and  mucus 
coats  for  about  an  inch,  being  somewhat 
diminished  in  caliber,  when  they  suddenly 
open  into  the  cavity  by  an  elliptical  orifice, 
so  that  if  the  bladder  be  distended,  the  sides 
of  the  orifice  are  stretched,  and  thus  closed. 

The  ureters  are  externally  covered  by  a 
cellulo-muscular  coat,  consisting  of  a  cellu- 
lar tissue,  with  muscular  fibres  arranged, 
partly  longitudinally  and  partly  circularly, 
the  latter  being  most  internally  situated. 
The  ureters  are  internally  lined  by  mucus 
membrane,  continuous  anteriorly  with  the 
renal  pelvis,  and  posteriorly  with  the  vesical 
lining. 

The  membrane  is  loosely  attached  to  the 
outer  coat,  and  thrown  into  longitudinal 
effaceablc  folds. 

BLADDER. 

The  bladder  is  dilatable  musculo-mem- 
branous  viscus,  destined  for  the  temporary 
retention  of  urine.  It  is  situated  during 
vacuity  entkely  within  the  pelvis,  but  when 
distended,  even  moderately,  its  fundus  en- 
croaches on  the  proper  abdominal  space. 

The  bladder  is  held  in  situation  by  the 
peritoneum  coming  off  from  the  rectum  and 
sides  of  the  pelvis,  so  as  to  form  a  serous 
fold,  which  also  encloses  the  vasa  deferentia 
and  vesiculsB  seminales.  Besides  this,  the 
bladder  is  supplied  with  true  ligaments,  as 
well  as  bounded  posteriorly  through  the  in- 
tervention of  the  urethra. 

The  shape  of  the  bladder  is  pyriform, 
approaching,  however,  to  a  sphere  when 
empty  or  partially  distended. 

It  presents  for  consideration  a  projecting 
anterior  portion  or  fundus,  a  middle  part  or 
body,  and  a  posterior  one,  or  neck.  The 
fundus  is  globular  and  regular,  having  fixed 
at  its  anterior  part  the  two  obliterated  um- 


bilical arteries,  and  the  remains  of  the 
urachus.  The  body  has  no  precise  limits, 
but  may  be  considered  as  that  portion  on 
which  the  bulbous  portions  of  the  vasa- 
deferentia  rest.  It  is  circular,  but  if  the 
bladder  be  much  distended,  it  bends  some- 
what backward  and  upward.  The  cervix 
vesicae  is  the  most  constricted  part  of  the 
organ,  and  marks  the  limit  between  the 
bladder  and  urethra. 

The  bladder  is  related  by  its  fundus  to 
the  iliac  flexures  of  the  colon,  inferiorly  to 
the  pudic  and  ischial  bones,  superiorly  to 
the  ureters,  vasa  deferentia,  vesiculee  semi- 
nales, and  middle  part  of  the  rectum. 

The  bladder  has  three  coats.  The  peri- 
toneal investment  is  merely  a  partial  one, 
as  it  is  reflected  from  the  body  on  to  the 
sides  of  the  pelvis.  It  covers  the  superior 
surface  almost  completely,  but  its  extent 
gradually  declines  laterally  and  inferiorly. 
The  attachments  contracted  by  the  perito- 
neum are  termed  false  ones.  Thus  we 
have  the  two  umbilical  arteries,  one  on  each 
side,  enclosed  by  peritoneum,  forming  the 
two  lateral  false  ligaments.  Then  the  ves- 
tige of  the  urachus  is  similarly  enveloped 
by  peritoneum,  and  constitutes  the  anterior 
false  ligament.  The  peritoneum  coming 
off  from  the  rectum  on  to  the  superior  sur- 
face of  the  bladder,  gives  rise  to  a  pouch, 
termed  the  recto-vesical  pouch,  or  cul-de- 
sac,  and  laterally  to  the  triangular  folds 
limiting  the  latter,  known  as  the  superior 
false  ligaments.  Behind  the  peritoneal  re- 
flection the  bladder  is  attached  to  the  rec- 
tum and  pelvic  parietes,  by  a  continuation 
of  the  pelvic  fascia,  which,  leaving  the 
inferior  surface  of  the  pelvis  at  the  symphi- 
sis pubis,  comes  on  to  the  bladder,  forming 
the  inferior  true  ligaments  of  the  latter ;  the 
fascia  is  then  continuous  on  to  the  rectum, 
blending  with  the  cellular  coat.  The  pelvic 
fascia  is  also  traced  on  to  the  prostate  and 
sides  of  the  bladder,  from  the  posterior  part 
of  the  obturator  foramen,  constituting  the 
lateral  true  ligaments. 

Beneath  this  fibro-serous  coat  are  muscu- 
lar fibres,  arranged  in  a  peculiar  manner. 
There  is  an  outer  longitudinal  set,  traceable 


118 


ANATOMY   AND    PHYSIOLOGY   OF 


from  the  cervix  forward  toward  the  body, 
where  the  fibres  diverge  and  become  oblique, 
and  some  even  circular ;  this  layer  is  prin- 
cipally developed  posteriorly.  The  inner  or 
circular  layer  is  not  arranged  in  concentric 
rings  ;  but  its  fibres,  beginning  at-  the  fund- 
us, appear  to  arise  from  various  centres  on 
the  surface,  and  to  be  taking  a  direction 
more  or  less  curved  in  difleront  parts,  so  as 
to  get  transversely  to  the  long  axis  of  the 
viscus,  and  thus  from  the  inner  side  have  a 
circular  appearance.  These  fibres  arc  more 
decidedly  circular  at  the  neck,  and  act  some- 
what like  a  sphincter.  Some  of  the  deeper 
fibres  at  the  neck  of  the  bladder  extend  for- 
ward to  each  orifice  of  the  ureter,  marking 
the  limit  of  the  vesical  trigon,  whose  office 
must  be  that  of  approaching  the  lips  of  the 
elliptical  apertures. 

The  mucus  coat  of  the  bladder  is  gener- 
ally more  or  less  coated  with  mucus  and 
epithelium,  which  guard  the  structm*e  from 
the  corroding  effects  of  the  secretion  it  has  to 
come  in  contact  with.  It  is  thrown  into 
numerous  folds,  taking  various  directions, 
but  principally  concentrical  toward  the 
fundus,  and  longitudinal  at  the  cervix,  all 
of  which  are  effaceable  by  distention  of  the 
bladder,  and  are  most  prominent  when  the 
latter  is  collapsed.  At  the  upper  part  of 
the  urethral  orifice  of  the  bladder  the  mucus 
lining  is  smooth  and  free  from  folds,  mark- 
ing out  a  triangular  space,  bounded  ante- 
riorly by  a  line  drawn  between  the  orifices 
of  the  ureters,  and  laterally  by  two  lines 
meeting  at  a  spot  at  the  superior  part  of 
the  vesical  orifice.  This  is  termed  the 
vesical  trigon.  At  its  apex  is  a  projecting 
fold  of  mucus  membrane  or  uvula  vesicae, 
which  seems  to  moderate  the  flow  of  urine 
into  the  urethra. 

The  bladder  is  supplied  with  blood  from 
the  internal  pudic,  and  its  veins  empty  into 
the  internal  pudic  vein. 

The  nerves  of  the  bladder  are  derived 
from  the  sympathetic,  and  partly  from  the 
two  last  sacral  pairs  which  supply  the  neck. 

The  lymphatics  go  to  glands  surrounding 
the  origin  of  the  ifiac  arteries,  termed  pelvic 
lymphatic  glands,  from  which  vessels  arise, 


communicating  anteriorly  with  the  recepta- 
culum  chyli. 

URETHRA. 

This  canal  in  the  male  subject  is  not  only 
purposed  for  the  passage  of  urine,  but  also 
transmits  the  products  of  the  generative  or- 
gans. It  extends  from  the  posterior  part  of 
the  bladder  to  the  glans  penis ;  but  we  shall 
only  occupy  ourselves  with  a  description  of 
the  intra-abdominal  or  pelvic  portion,  which 
terminates  at  the  bulb  of  the  penis  or  ischial 
arch. 

It  is  continuous  anteriorly  with  the  blad- 
der, attached  to  the  rectum  arid  sides  of  the 
pelvis  by  fascia  and  loose  cellular  tissue 
and  muscles. 

The  urethra  is  cylindrical,  of  considerable 
length,  and  its  coats  of  no  mean  thickness. 
The  pelvic  portion  of  the  vu-ethra  is  gener- 
ally about  three  or  four  inches  long,  taking 
a  direction  backward  and  somewhat  up- 
ward. 

It  is  related  superiorly  to  the  vesiculee 
seminales,  middle  lobe  of  the  prostate,  and 
posteriorly  it  comes  in  contact  with  the  rec- 
tum, but  separated  from  it  laterally  by 
Cowper's  glands. 

The  first  or  prostatic  portion  of  the  ure- 
thra is  purely  membranous,  strengthened  by 
cellular  tissue  and  a  continuation  of  the 
fibres  of  the  bladder,  the  circular  ones  in 
particular,  which  are  abundant  anteriorly. 
The  posterior  two-thirds  of  the  pelvic  por- 
tion of  the  urethra  are  covered  by  a  thick 
red  muscular  layer,  which  completely  encir- 
cles it,  with  the  exception  of  that  part 
coming  in  contact  with  Cowper's  glands. 
This  muscle  is  continuous  behind  wdth  the 
muscular  fibres  of  the  penis,  which  consti- 
tute the  accelerator  urinae.  These  fibres 
are  externally  mixed  with  longitudinal  ones, 
a  portion  of  which  are  merely  the  inner  or 
inferior  bundles  of  the  retractor  ani,  whilst 
others  are  derived  from  the  triangularis 
penis ;  both  of  these  muscles  tend  to  fix  the 
urethra.  Postero-superiorly  the  fibres  en- 
cii'cling  the  urethra  are  blended  with  the 
external  anal  sphincter.  The  retractor  penis, 
which  gets  attached  to  the  sacral  bone,  is  a 


THE   HOESE. 


119 


white  muscle  also,  affording  fixity  to  the 
pelvic  portion  of  the  urethra. 

Beneath  the  muscular  tunic  of  the  urethra 
we  find  a  loose  cellular  tissue,  and  pos- 
teriorly also  some  erectile  structure  continu- 
ous on  to  the  penis. 

On  slitting  open  the  pelvic  portion  of  the 
urethra,  to  examine  its  mucus  membrane, 
we  find  that  it  is  smooth,  glistening,  and 
thrown  into  longitudinal  folds.  It  is  antero- 
superiorly  raised 'by  the  sub-mucus  tissue 
into  a  permanent  ridge,  termed  the  crest  of 
the  urethra  or  verumontanum.  This  has  a 
depression  about  its  middle,  and  on  each 
side  are  the  elliptical  orifices  of  the  ejacula- 
tory  ducts,  surrounded  by  the  openings  of 
the  prostatic  ducts.  Posteriorly  and  later- 
ally are  little  papillated  projections,  pierced 
by  ducts  emanating  from  Cowper's  glands. 
These  tubular  processes  are  arranged  in  two 
parallel  lines  longitudinally  to  the  course  of 
the  uretln^a. 

The  pelvic  portion  of  the  urethra  is  sup- 
plied with  blood  from  the  internal  pudic, 
and  the  veins  empty  into  the  vessel  of  the 
same  name.  Its  nerves  are  derived  from 
the  two  last  sacral  and  accompanying  sym- 
pathetic filaments. 

The  lymphatics  of  the  pelvic  urethra  are 
similarly  disposed  to  those  of  the  bladder. 

GENERATIVE  ORGANS  OF  THE  MALE. 

The  last  division  of  our  subject  is  that 
of  the  abdominal  generative  organs,  only  a 
part  of  the  generative  system,  and  consist- 
ing in  the  vasa  deferentia,  vesiculae  semin- 
ales,  prostate  and  Cowper's.  glands. 

VASA    DEFERENTIA. 

There  are  two  vasa  deferentia,  one  from 
each  testicle,  for  the  passage  of  semen  to 
seminal  reservoirs. 

The  vas  deferens  arises  from  the  posterior 
part  of  the  epididymis  or  globus  minor, 
passing  through  the  inguinal  canals,  and 
reaching  the  abdomen ;  it  is  situated  in  the 
sub-serous  tissue,  taking  a  course  upward, 
backward,  and  inward,  to  reach  the  brim 
of  the  pelvis ;  then,  crossing  the  com-se  of 


the  ureters,  it  gets  on  to  the  bladder,  where 
it  is  dilated,  and  forms  the  bulbous  por- 
tion. 

Its  attachments  are  serous  and  cellular  to 
the  various  parts  mentioned,  whilst  its  pos- 
terior part  is  connected  with  the  urethra. 

The  vas  deferens  is  related,  in  its  com-se 
from  the  inguinal  canal,  to  the  bladder ; 
after  it  leaves  the  constituents  of  the  cord, 
with  the  parietes  of  the  abdomen  ;  crossing 
the  under  surface  of  the  iliac  vessels,  and 
reaching  the  bladder  on  the  inner  side  of 
the  ureter ;  also  lying  internally  to  the 
seminal  vesicles,  and  the  terminating  portion 
being  covered  by  the  prostate. 

The  structure  of  the  vas  deferens  is  simi- 
lar throughout,  with  the  exception  of  the 
greater  thickness  of  its  coats  at  the  bulbous 
portion,  being  thinnest  where  it  contributes 
to  form  the  ejaculatory  duct. 

This  tube,  of  very  various  length,  is  con- 
stituted of  an  outer  cellular  investment,  not 
requiring  pecuUar  notice ;  of  an  intermediate 
contractile  and  elastic  tunic;  and,  as  its 
name  implies,  is  composed  of  muscular 
fibres  and  elastic  tissue,  arranged  in  two 
layers,  i.  e.,  an  outer  longitudinal  and  an  in- 
ner circular  one,  which  are  easily  perceived. 

The  internal  or  mucus  lining  is  thrown 
into  longitudinal  folds,  in  the  narrow  part 
of  the  duct ;  but  in  the  bulbous  part  it  forms 
permanent  rugae,  taking  various  directions, 
so  as  to  enclose  irregular  interspaces. 

The  vas  deferens  is  supplied  with  blood 
principally  from  the  artery  of  the  cord,  al- 
though the  epigastric  furnishes  a  twig  to  it 
as  well.  The  bulbous  portion  is  supplied 
also  by  vessels  of  no  small  calibre  from  the 
iliacs. 

Its  nerves  are  from  the  sympathetic,  as 
well  as  from  the  second  and  thkd  lumbar. 

VESICULJE    SEMINALES. 

The  seminal  vesicles  are  one  on  each  side 
of  the  bladder,  and  act  as  receptacles  for 
the  semen. 

Each  seminal  vesicle  extends  from  behind 
foi-ward,  upward,  and  outward,  being  ex- 
ternal  to   the   bulbous   portion  of  the  vas 


EXPLANATION   OF  FIGUEE  XIII. 


THE    SUPERFICIAL  LAYER  OF    MUSCLES  TAIvEN  FROM    THE    BODY  OF   THE  HORSE, 
SO  AS  TO  EXPOSE  THOSE   MUSCLES  WHICH  ARE   MORE  DEEPLY   SEATED. 

THE  HEAD  A^^D  NECK. 

a.     Buccinator. 
h.     Caninus. 

c.  Retractor  labii  inferioris. 

1,  1.     Orbicularis  oris. 

2,  2,  2.     Complexus  major. 

3,  3.     Traclielo  mastoideus. 

4,  4.     Subscapulo  hyoideus. 

5,  Steriio  maxillaris. 

6,  6.     Sterno  th}TO-hyoideus. 

7,  Jugular  vein. 

8,  Carotid  artery,  with  the  eighth  paii",  and  sympathetic  nerves. 

9,  Trachea. 
10.  Scalenus. 

THE  FOEE  LIMBS. 

1.  Scapulo  ulnarius. 

2.  Caput  magnum  of  the  triceps  extensor  brachii. 

3.  Caput  medium  of  the  same  muscle. 

4.  Anconeus. 

5.  Flexor  bracliii. 

6.  Extensor  metacarpi. 

7.  Extensor  pedis. 

8.  Extensor  metacarpi  obliquus. 

10.  Flexor  metacai'pi  externus. 

11.  Perforans  and  perforatus. 

12.  Ulnarius  accessorius. 

13.  Flexor  metacarpi  internus. 

14.  Flexor  metacariji  medius. 

15.  Perforans  and  perforatus. 

16.  Extensor  metacarpi. 
B.  B.  Radius. 

THE  TRUNK  AND  BACK. 

A.  Scapula. 

F.  F.  Longissimus  dorsi. 

O.  SpinaHs  dorsi. 

a,  a.  Intercostals. 

h,  b.  SuperiiciaHs  costarum. 

e,  e.  Rectus  Abdominis. 

d,  d.  Transversalis  abdominis. 

€,  c,  e.  Obliquus  internus  abdominis. 

/.  Hollow  in  the  longissimus  dorsi,  which  part  of  the  gluteus  maximus  once  filled. 


EXPLANATION    OF   FIGURE    XIII.    CONTINUED. 

nAUNCn  AM)  IXDOD  EXTEEMITY. 

C.  lUum. 

D.  Ischium. 

E.  Tibia. 

1.  Sacro  sciatic  ligament. 

2.  Spliincter  ani. 

3.  Depressor  coccygis. 

4.  Muscles  of  the  tail. 

5.  5.    Triceps  abductor  tibialis. 

6.  Vastus  externus. 

7.  Rectus. 

8.  Gastrocnemius  muscles. 
iTT  Plantai-ius. 

10.  Extensor  pedis. 

11.  Peroneus. 

12.  Flexor  pedis  perforans. 

13.  Insertion  of  the  gracilis. 

14.  Gastrocnemii  muscles. 

15.  Flexor  pedis  accessorius. 

16.  Coui'se  of  the  perforans  tendon,  inside  tKe  os  c&'cis  of  the  hock  joiixt. 

17.  Insertion  of  the  gastrocnemius  externus  into  the  point  of  the  hock. 

18.  18.     Popliteus  muscles. 

19.  Extensor  pedis. 


THE   HORSE. 


121 


Cowper's  glands  are  covered  by  the  tri- 
angularis penis  of  each  side  :  they  are 
about  the  size  of  a  filbert. 

Their  structure,  as  apparent  to  the  naked 
eye,  is  similar  to  that  of  the  prostate  in 


every  respect,  only  the  excretory  ducts  are  prostate 
11 


ten  or  twelve  in  number  for  each  gland 
and  linearly  disposed  on  each  side  of  the 
pelvic  urethra. 

Cowper's  glands  are  supplied  with  ves- 
sels and  nerves  from  the  same  source  as  the 


ORGANS  OF  GENERATION. 


TESTICLES    AND    SCROTUM. 

The  preparation  of  the  seminal  fluid  is 
the  office  of  two  oval  glandular  bodies,  called 
the  testes  or  testicles ;  they  are  suspended 
in  a  portion  of  the  common  integument, 
termed  the  scrotum,  by  means  of  the  sper- 
matic cord  and  cremaster  muscle. 

The  scrotum  is  composed  of  the  common 
integument,  sub-cellular  tissue,  and  elastis 
muscle,  (the  fibres  of  the  latter  run  in  a  lon- 
gitudinal direction,  from  the  cellular  sub- 
stance of  the  sheath,  to  the  base  of  the 
penis),  and  lastly  the  tunica  vaginalis, 
which  is  a  prolongation  of  the  peritoneum. 

The  testicle  has  a  peritoneal  covering, 
termed  tunica  vaginalis  testes,  and  also 
another  distinct  tunic  termed  tunica  albu- 
ginea.  The  substance  of  the  testicle  is  ex- 
tremely vascular,  and  the  ultimate  branches 
of  its  spermatic  arteries  are  collected  into 
small  bundles  of  fine  convaluted  vessels, 
separated  from  one  another  by  septulae,  or 
membranous  partitions.  From  these  the 
vasa  seminifera,  or  beginnings  of  excretory 
ducts,  take  their  origin,  and  gradually  unite 
to  form  a  smaller  number  of  canals  of 
larger  diameter,  but  exceedingly  tortuous  in 
their  course.  The  testicle  is  also  supplied 
with  nerves  and  absorbents,  secretory  and 
excretory  vessels. 

SPERMATIC    CORD.* 

The  spermatic  cord,  the  substance  by 
means  of  which  the  testicle  is  connected  with 
the  abdomen,  and  by  means  of  which  it  is 
suspended  within  its  scrotal  cavity,  is  com- 
posed in  the  following  manner :  1st.  It  has 
four  coverings  ;  there  is  immediately  under- 
neath the  skin  the  faschia  superficialis  ;  next, 
the  cremaster  muscle ;  thirdly,  the  tunica 

*  Percivall. 


vaginalis;  and  lastly,  the  tunica  vaginalis 
reflexa.  Within  the  cavity  formed  by  the 
vaginal  tunic,  it  is  that  the  intestine  protrudes 
in  inguinal  and  scrotal  hernia ;  the  hernial 
coverings,  consequently,  exclusive  of  the  sac, 
will  be  the  faschia  and  cremaster  muscle. 

2ndly.  The  constituent  parts  of  the  cord 
itself,  are :  a.  The  arteries,  which  are  two 
in  number ;  the  artery  of  the  cord,  a  small 
branch  of  the  external  iliac,  which  ramifies 
and  expands  itself  upon  the  cord  ;  and  the 
spermatic  artery,  which,  as  soon  as  it 
reaches  the  internal  ring,  enters  the  inguinal 
canal,  runs  down  the  posterior  part  of  the 
cord,  growing  tertuous  as  it  descends,  ser- 
pentines along  the  superior  border  of  the 
testes,  between  it  and  the  epididymis,  winds 
round  the  anterior  end  of  the  gland,  and 
lastly  reaches  the  convex  border,  where  it 
becomes  extremely  convoluted,  and  whereto 
its  branches  are  principally  distributed.  In 
its  descent  it  detaches  small  unimportant 
twigs  to  the  adjacent  parts ;  and,  as  it  ap- 
proaches the  testicle,  becomes  surrounded 
by  an  assemblage  of  venous  vessels,  b. 
The  veins  accompany  their  corresponding 
arteries,  and  they  indeed  may  be  said  to 
make  up  the  principal  bulk  of  the  cord, 
for  they  are  not  only  numerous,  but  large 
and  flexuous,  and,  as  they  approach  the 
testicle,  form  a  sort  of  plexus,  which  has  got 
the  name  of  corpus  pampiniforme :  they 
return  their  blood  into  the  posterior  vena 
cava.  c.  The  nerves,  which  are  derived 
from  the  hypogastric  plexus,  also  accom- 
pany the  spermatic  artery :  they  are  small, 
but  sufficiently  numerous.  Though  the 
testicle  does  not  possess  any  very  great  sen- 
sibility in  health,  we  may  vouch  for  its 
being  acutely  sensitive  in  a  state  of  disease. 
d.  Absorbents  exist,  both  large  and  numer- 
ous, in  the  cord.     They  are  readily  found 


ANATOMY  ANJ  PHYSIOLYGY  OF  THE  HORSE. 


123 


alongside  of  the  venous  trunks ;  and  not 
infrequently  may  be  filled  by  introducing 
mercury  into  the  spermatic  artery,  c.  The 
VAS  DEFERENS,  though  a  constituent  of  the 
cord,  takes  at  first  a  solitary  course,  remote 
from  the  blood  vessels.  The  duct  issues 
from  the  summit  of  the  head  of  the  epidi- 
dymis, beginning  in  a  series  of  convolu- 
tions gradually  unwinding  as  it  proceeds ; 
it  takes  an  obfique  course  nearly  as  high  as 
the  external  ring,  where  it  joins  the  blood 
vessels,  and  continues  to  accompany  them 
posteriorly  through  the  inguinal  canal :  at 
the  internal  ring  it  leaves  them,  turns 
inward  and  ascends  into  the  pelvis,  where 
we  find  it  creeping  along  the  side  of  the 
bladder  infolded  in  peritoneum  to  get  to  the 
cervix,  crossing  under  its  course  first  the 
umbilical  artery  and  then  the  ureter;  at 
length  it  terminates  by  rather  a  contracted 
orifice  within  the  mouth  of  the  duct  of  the 
vesicula  seminalis,  just  behind  a  little  emi- 
nence in  the  urethra  —  the  capat  g-alinag-inis, 
about  an  inch  posteriorly  to  the  cervix  of 
the  bladder.  Within  the  inguinal  passage 
the  duct  is  accompanied  by  the  artery  of 
the  vas  deferens,^  long  slender  branch  of  the 
epigastric.  Its  canal,  flexuous  until  the 
duct  has  joined  the  cord,  but  straight  in  its 
subsequent  course,  is  not  uniform  through- 
out in  caliber ;  the  area  of  its  tortuous  part 
is  large,  but  as  it  becomes  straight  it  grows 
contracted :  having  entered  the  pelvis,  it 
gradually  enlarges  again,  and  acquires  un- 
usual volume  in  running  along  the  side  of  the 
bladder ;  and  the  canal  of  the  enlarged  por- 
tion presents  a  riticulated  structure,  which 
gives  its  exterior  an  irregular,  tuberculated 
appearance ;  the  most  contracted  part  is 
that  in  union  with  the  duct  of  the  vesicula 
seminalis,  which  is  a  comparatively  small 
cylindrical  conduit.  The  parietes  of  the 
duct  are  so  remarkably  thick  and  firm  to 
the  feel,  that  we  distinguish  it  at  once  by 
the  fingers  from  the  other  parts  of  the 
cord  :  they  consist  of  tw^o  tunics ;  the  ex- 
ternal one  (in  which  its  main  thickness  con- 
sists) is  white,  fibrous,  and  approaches  in 
appearance  to  cartilage ;  the  internal  one  is 
thin  and  fine  in  texture,  muco-membranous 


in  its  nature,  and  here  and  there  incloses  a 
reticulated  structure.  The  different  consti- 
tuent parts  of  the  cord  are  connected  alto- 
gether by  cellular  substance,  destitute  of 
any  fat ;  and  from  the  circumstance  of  the 
parts  in  general  being  more  bulimy  below  the 
ring,  the  cord  increases  in  breadth  and 
thickness  as  it  approaches  the  testicle. 

THE    EPIDIDYMIS. 

The  epididymis  is  extended  along  the  su- 
perior border  of  the  testicle,  upon  which  it 
rests,  and  to  wliich  it  is  connected  by  the 
tunica  vaginalis  reflexa.  Its  ends  are  bulky 
in  comparison  to  its  middle  :  that  receiving 
the  vasa  efterentia,  the  smaller  one,  is  the 
caput  or  globus  minor;  the  other,  giving 
rise  to  the  vas  deferens,  is  the  globus  major, 
the  part  farriers  call  the  7iut.  The  interior 
of  this  appendage  to  the  testicle  exhibits  a 
structure  entirely  vascular.  The  vasa  ef- 
ferentia  unite  and  re-unite  until  they  form 
a  single  duct,  of  whose  numberless  and 
very  remarkable  convolutions  the  globus 
major  is  entirely  constituted :  these  tortu- 
osities (which,  when  squeezed,  freely  emit 
semen)  wiU  admit  of  being  unwound  for  a 
considerable  extent,  so  as  to  have  the 
length  of  the  duct  calculated  with  very 
tolerable  exactness  from  beginning  to  end, 
which  has  been  found  to  amount  to  several 
yards.  It  is  small  at  its  formation,  but  grows 
imperceptibly  larger  in  making  its  manifold 
windings  and  turnings,  until  at  length  it 
assumes  the  size  of  the  vas  deferens,  in 
which  it  ends.  Its  various  convolutions  are 
connected  together  by  cellular  membrane, 
and  are  interspersed  with  a  sparing  supply 
of  blood  vessels. 

The  course  of  the  semen  is  this:  It  is 
secreted  by  the  capillary  coils  of  the  sper- 
matic artery,  from  which  it  is  received  by 
the  tubili  seminiferi:  these  tubes  carry  it 
into  the  rete,  and  the  rete  discharges  it 
through  the  vasa  efferentia  into  the  epididy- 
mis, from  which  it  is  conducted  by  the 
vas  deferens  into  the  urethra. 

Formation  and  Descent.  —  It  is  a  singu- 
lar fact,  that  the  organs  whose  structures 
we  have  been  investigating,  are  originally 


124 


ANATOMY   AND   PHYSIOLOGY   OF 


formed  in  a  situation  remote  from  that  in 
which  they  are  destined  to  carry  on  their 
functions;  "the  colt  has  no  testicles,"  is 
the  common  observation  of  the  unim- 
formed  on  these  matters  ;  and  we  know 
ourselves  that  the  purse  is  without  them, 
bn.t  we  know,  in  addition,  that  they  exist 
ready-formed  within  the  abdomen,  and  that 
they  will  descend  at  a  certain  period  of  age 
into  the  proper  receptacle,  the  scrotum. 
During  the  foetal  state  we  jfind  the  testicles 
more  or  less  developed,  tinged  with  a  blush 
of  red,  lodged  beneath  the  psoas  muscles, 
in  contact  with  the  inferior  borders  of  the 
kidneys,  covered  and  retained  in  their  situ- 
ations by  peritoneum,  and  concealed  by  the 
intestines  around  them.  Here  they  receive 
their  arteries  from  the  contiguous  trunk  — 
the  posterior  aorta ;  the  vasa  deferentia 
run  forward  to  them,  and  the  cremosters 
likewise  turn  forward  instead  of  backward ; 
there  being  at  this  time  no  such  thing  as  a 
spermatic  cord.  Thus  placed,  the  testicle 
may  be  regarded  as  one  of  the  glands  of 
the  abdomen ;  indeed  it  has  considerable 
similarity  to  the  kidney  —  receiving  its  ves- 
sels from  the  same  contiguous  source,  and 
sending  a  long  duct  backward  into  the 
cavity  of  the  pelvis  ;  nor  does  there  appear 
any  conclusive  reason  W'hy  it  should  not 
perform  the  same  office  in  that  situation 
that  it  does  in  the  scrotum,  and  particu- 
larly since  it  is  known  that  in  birds  the  tes- 
ticles remain  within  the  abdomen  during 
life.  From  the  part  where  the  blood  ves- 
sels enter,  we  find  growing  a  whitish  sub- 
stance, extending  backward,  diminishing 
in  breadth  as  it  recedes,  passing  through 
the  ring  where  the  filus  of  the  cremoster 
may  be  traced  upon  it,  and  whence  it  is 
prolonged  into  the  scrotum,  growing  nar- 
row^er  and  narrower  until  it  vanishes ;  this 
substance,  regarded  by  some  simply  as  a 
ligament,  was  considered  by  ]\Ir.  Hunter 
as  the  gubernaculum  or  pilot,  by  means  of 
which  the  testicle  is  directed  in  its  passage 
from  the  abdomen  into  the  scrotum.  Quit- 
ting the  spot  where  it  has  been  formed  and 
matured,  the  testicle  gradually  retrocedes, 
guided  by  the  gubernaculum,  until  it  ar- 


rives on  the  internal  ring,  which,  at  this 
time  (like  every  other  part  of  the  parietes) 
is  closed  by  peritoneum ;  this  temporary 
obstruction  it  overcomes  by  drawing  the 
membrane  down  along  with  it  through  the 
ring,  and  carrying  the  pouch  made  thereby 
down  into  the  scrotum  ;  the  gubernaculum 
at  the  time  undergoing  a  complete  in- 
version. This  accounts  for  the  production 
of  the  tunica  vaginalis,  and  explains  how 
that  membrane  comes  to  be  doubled  or  re- 
flected; the  testicle,  receiving  originally  (as 
an  abdominal  viscus)  one  close  adherent 
peritoneal  tunic,  and  acquiring  another 
which  forms  a  loose  covering  as  it  passes 
through  the  ring,  must  necessarily  have 
two ;  and  since  both  are  derived  from  one 
and  the  same  membrane,  it  follows  that 
one  must  be  a  continuation  of  the  other. 
These  elongations  of  membrane,  though 
everywhere  in  contact,  are  prevented  from 
adhering  together  by  a  continual  exhala- 
tion of  the  natm-al  serous  secretion.  Any 
interval  that  might  subsist  between  them, 
in  course,  communicates  with  the  cavity  of 
the  abdomen,  through  the  ring,  a  part  that 
remains  open  through  life :  this,  however, 
is  not  the  case  with  man  —  in  his  body  the 
communication  is  cut  off,  after  the  testicles 
have  descended,  by  a  natural  contraction 
and  obliteration  both  of  the  ring  and  the 
inguinal  passage.  In  many  instances,  one, 
in  some  few,  both  of  the  testicles,  are 
known  to  have  remained  within  the  belly 
through  life.  As  we  are  unacquainted  wdth 
the  immediate  cause  of  their  descent,  so 
we  are  unable  to  give  any  rational  explana- 
tion of  this  phenomenon.  I  have  under- 
stood, that  in  many  of  these  cases  the 
glands  have  been  found  to  be  but  imper- 
fectly developed  :  this,  however,  is  not  with- 
out exception. 

Period  of  Descent.  —  Most  animals  have 
their  testicles  wdthin  the  scrotum  at  the 
period  of  birth.  In  the  human  foetus  they 
begin  to  move  about  the  seventh  month  ; 
about  the  eighth  they  reach  the  groins  ;  and 
before  birth  they  arrive  in  the  scrotum. 
In  the  horse,  they  pass  through  the  ring 
about  the  sixth    or  seventh  month  before 


THE    HORSE. 


125 


birth,  and  are  found  within  the  scrotum  at 
the  period  of  parturition.  In  some  cases, 
one  testicle  will  not  make  its  appearance 
for  some  time  after  the  other ;  and  as  the 
operation  for  castration  is  seldom  long  de- 
layed, this  will  account  for  the  rigs  (as 
horses  having  but  one  testicle  are  called) 
with  which  we  meet  every  now  and  then. 
Again,  instances  are  not  wanting  in  which 
one  testicle  has  descended  to  the  ring  and 
there  remained  through  life.* 

PENIS. 

The  penis  is  composed  of  the  two  corpora 
cavermosa :  head,  or  glans  penis :  corpus 
musculosum  urethra,  and  the  plexus  veno- 
sus.  The  corporo  cavermosa  make  up  the 
bulk  of  the  organ,  they  extend  from  the 
pelvis  to  the  glans  penis  ;  at  the  ischial  arch 
they  are  invested  with  fibres  of  the  erectors 
penis,  and  are  strengthened  and  confined  to 
the  pubes  by  the  suspensory  ligaments.  It 
is  supplied  with  blood  from  a  branch  of 
the  obturaler  arter,  by  means  of  the  inter- 
nal pudic  artery.  Its  nerves  are  termed 
pudic,  so  also  are  the  veins. 

The  glans  is  composed  of  a  soft  spongy 
tissue,  highly  elastic  and  distensible,  and 
remarkable  as  the  seat  of  the  plexus  venosus 
penis :  the  latter  structure  presents  itself  in 
the  form  of  a  venous  conglomeration,  and 
in  the  erect  state  of  the  organ  constitutes 
its  chief  bulk. 

URETHRA. 

The  urethra  is  a  muco-membranous  canal 

*  In  a  communication  I  have  been  favored  with  from 
'Mx.  Brettargh  (which  I  have  inserted  in  the  second  vol- 
ume of  The  Veterinarian),  is  contained  the  following 
information  on  this  subject :  "  Colts  are  foaled  with  their 
testicles  in  the  scrotum,  which  remain  there  (in  ordinary 
cases)  until  the  fifth  or  sixth  month,  Avheii  they  are  taken 
up  between  the  internal  and  external  abdominal  rings, 
and  there  remain  until  the  eleventh,  twelfth  or  thirteenth 
month,  all  depending  upon  the  degree  of  keep,  as  in  some 
that  are  well  fed  the  testicles  can  at  all  times  be  found  in 
the  scrotum.  Were  the  testicles  drawn  up  into  the  abdo- 
men, they  would  be  too  large  to  pass  through  the  inter- 
nal abdominal  ring  at  the  time  they  are  wanted  to  prepare 
for  secretion ;  which  is  occasionally  the  case,  and  at  once 
accounts  for  our  meeting  with  horses  that  are  said  to  have 
but  one  stone.  I  have  seen  one  instance  where  both  were 
wanting  in  the  scrotum  at  four  years  old." 


averaging  in  length,  in  the  unerected  state 
forty -eight  inches;  it  extends  from  the  ante- 
rior part  of  the  glans  penis  to  the  neck  of 
the  bladder ;  its  use  is  to  afford  a  passage 
for  the  urine  and  seminal  fluid. 

FEMALE    ORGANS    OF    GENERATION. 

The  vulva  or  pudendum  comprises  the 
prominence  and  fissure,  commencing  imme- 
diately beneath  the  anus,  and  extending 
downwards  some  four  or  five  inches.  The 
fissure  is  longest  and  most  conspicuous  in 
breeding  mares.  The  space  between  the 
anus  and  vulva  is  termed  perineum.  The 
prominences  on  each  side  of  the  vulva  are 
called  labia  frudinde.  They  owe  their 
bulk  principally  to  muscular  and  fatty  sub- 
stance, and  cellular  tissue. 

The  commissures  are  the  parts  uniting  the 
labia  above  and  below.  The  superior  or 
upper  commissure  is  extended  to  a  sharp 
angle,  and  joins  the  perineum;  the  lower 
portion  is  rounded  off,  and  is  bounded  by  a 
hollow,  at  the  bottom  of  which  is  lodged 
the 

Clitoris.  —  This  is  brought  into  view  im- 
mediately after  staling:  it  bears  a  close 
comparison  to  the  head  of  the  male  penis, 
and,  like  the  latter,  is  susceptible  of  sensual 
enjoyment.  To  the  clitoris  belong  a  pan- 
of  muscles  named  erector  clitoris.  They 
take  their  origin  from  the  perineum.  Their 
office  is  to  erect  that  body,  and  protrude  it 
into  the  vagina  in  the  act  of  coition. 

The  internal  parts  are  the  vagina,  uterus, 
Fallopian  tubes,  fimbrioB,  and  ovaria.  The 
vagina  is  a  musculo-membranous  canal,  of 
large  dimensions,  extending  from  the  vulva 
to  the  uterus  or  womb. 

It  is  situated  within  the  pelvis,  having 
the  bladder  below  and  the  rectum  above  it, 
to  both  of  which  it  has  cellular  attach- 
ments, in  addition  to  the  reciprocal  connec- 
tion with  the  peritoneum.  To  the  rectum 
it  is  closely  and  firmly  attached  by  cellular 
membrane. 

The  figure  of  the  vagina,  when  it  is  dis- 
tended, is  that  of  an  oblong  cylinder ;  but 
in  the  collapsed  state,  its  sides  are  in  con- 
tact, and  it  will  vary  its  form  according  to 


126 


ANATOMY   AND   PHTSIOLOGY   OF 


the  full  or  empty  condition  of  the  bladder. 
The  largest  part  of  the  canal  is  the  poste- 
rior ;  there  it  exceeds  the  dimensions  of  the 
bladder. 

The  length  of  the  canal  is  about  eighteen 
inches.  Its  course  is  horizontal,  and  rather 
shows  an  inclination  to  the  curve  of  the 
rectum. 

The  vagina,  at  its  commencement  from 
the  vulva,  is  much  thicker  in  its  walls  than 
elsewhere ;  in  composition  it  is  partly  mus- 
cular and  partly  membranous.  The  orifice 
of  it  is  clothed  in  that  strong,  red,  circular, 
fleshy  band,  which  forms  the  sphincter 
vagina ;  and  the  adjoining  part  of  the  canal 
is  also  encircled  by  some  considerable  fleshy 
covering,  and  thickly  coated  with  muscular 
fibres.  Farther  forward  than  this  the  vagina 
is  composed  of  membrane. 

The  JSIembrane  of  the  Vagina.  —  The  part 
of  which  it  is  constituted  is  one  of  the 
mucus  class,  and  one  that  possesses  consid- 
erable density,  extensibility,  and  resistance. 
Its  exterior  surface  is  rough.  Its  interior 
is  smooth,  and  has  a  pale  pinkish  cast; 
unless  the  mare  be  under  the  venereal  oes- 
trum, and  then  its  redness  is  heightened, 
and  its  secretion  augmented.  In  the  ordin- 
ary state,  this  membrane  is  thrown  into 
folds,  larger  in  breeding  mares  than  in  others, 
technically  called  rugae. 

Considerably  in  advance  of  the  clitoris  is 
an  opening  leading  from  the  lower  part  of 
the  canal,  large  enough  to  admit  with  ease 
any  one  of  the  fingers :  this  is  the  orifice  of 
the  meatus  urinarius,  or  outlet  of  the  blad- 
der: it  is  guarded  by  a  doubling  of  the 
vaginal  membrane,  which  hangs  over  it,  and 
serves  the  purpose  of  a  valve. 

The  large  and  conspicuous  protuberance 
at  the  bottom  of  the  vagina,  is  the  mouth 
of  the  uterus. 

The  uterus,  or  womb,  is  a  hollow  mus- 
culo-membranous  organ,  united  to  the  ante- 
rior part  of  the  vagina,  and  is  destined  for 
the  reception  of  the  foetus.  We  distinguish 
the  uterus  by  the  body,  horns,  neck,  and 
mouth.  The  body  is  the  oblong  or  cylin- 
drical part,  growing  out  of  the  anterior  por- 
tion of  the  vagina,  in  the  centre  of  which 


it  is  terminated  internally  by  the  os-uteri, 
or  mouth  of  the  womb  ;  it  gives  origin,  in 
front,  to  the  horns.  This  part  lies  wholly 
within  the  pelvis,  between  the  bladder  and 
rectum,  and  is  entirely  covered  by  peri- 
toneum. 

The  cornua,  or  horns,  rise  from  the  body 
of  the  uterus,  and  diverge  towards  the  loins. 
Their  length  and  size  will  be  much  greater 
in  breeding  marcs  than  in  others.  In  figure 
they  are  cylindrical ;  they  bend  upward  in 
their  course,  and  terminate  in  round  extrem- 
ities, to  which  are  loosely  appended  the 
ovaries,  or  testicles,  through  the  medium  of 
the  Fallopian  fubes. 

The  cervix,  or  neck,  of  the  uterus  is  the 
rugose  portion,  protruded  backward  into  the 
cavity  of  the  vagina,  which  has  a  flower- 
like appearance,  and  can  only  be  seen  in  a 
virgin  uterus  in  the  undistended  state ;  dur- 
ing gestation  it  undergoes  a  remarkable 
change. 

Independently  of  its  union  with  the 
vagina,  the  uterus  is  confined  in  its  place 
by  two  broad  portions  of  peritoneum, 
which  attach  it  to  the  sides  of  the  pelvis, 
named  the  lateral  ligaments  of  the  uterus. 
During  the  period  of  gestation,  the  uterus 
experiences  considerable  extension.  The 
Fallopian  tubes  are  two  trumpet-shaped 
canals,  having  a  remarkable  serpentine 
course ;  running  within  the  folds  of  the 
iigamenta  lata,  from  the  extremities  of  the 
horns  to  the  ovaries. 

The  tube  commences  by  an  aperture  in 
the  cornu,  having  an  elevated  whitish  mar- 
gin, which  is  scarcely  large  enough  to  admit 
a  small  silver  probe :  from  this  it  proceeds 
forw^ard,  folded  in  peritoneum,  and  ex- 
tremely convoluted,  until  it  reaches  the 
ovary,  to  which  it  becomes  attached;  it 
then  begins  to  enlarge  in  its  diameter, 
grows  less  convoluted,  and  serpentines  along 
the  lower  side  of  the  ovary ;  it  afterwards 
ends  in  a  fringed  doubling  of  membrane. 

The  internal  membrane  of  the  tubes  is 
similar  to  that  of  the  uterus. 

The  ovari,  or  female  testicles,  are  two 
egg-shaped  bodies,  situated  farther  forward 
than  the  Fallopian  tubes,  within  the  cavity 


THE  HORSE. 


127 


of  the  abdomen :  they  receive  close  cov- 
erings, and  are  loosely  attached  to  the 
spine. 

These  bodies  are  about  the  size  of  v^al- 
nuts.  They  are  not  regular  oviform ;  they 
have  deep  fissures  on  their  sides  ;  they 
bear  a  resemblance,  at  first  view,  to  the 
testicles  and  their  ducts  in  the  male. 

Internally,  the  ovaries  are  composed  of  a 
whitish  spongy  substance,  in  which  are,  in 
some  instances,  found  little  vesicles,  con- 
taining a  yellowish  glairy  fluid,  in  others 
one  or  more  dark  yellow  or  brownish  sub- 
stances, named  corpora  lutea :  the  vesicles 
are  the  ova,  which,  from  impregnation,  re- 
ceive further  development;  the  corpora 
lutea  denote  the  parts  from  which  vesicles 
have  burst,  and  consequently  only  exist  in 
the  ovaries  of  those  mares  whose  organs 
have  been  engaged  in  the  generative  pro- 
cess. Prior  to  the  age  of  sexual  intercourse, 
these  bodies  are  small  and  white ;  but,  as 
soon  as  the  season  of  copulation  is  at  hand, 
they  grow  large,  redden  externally,  and 
present  many  yellow  spots  or  streaks 
through  their  substance. 

Mammce,  though  unconnected  with  the 
uterus,  anomatically  speaking,  are  in  func- 
tion concurring  to  the  same  important  end. 
The  mammae,  vulgarly  called  udder,  are 
two  flattened  oval-shaped  bodies,  depend- 
ing, between  the  thighs,  from  the  posterior 
and  inferior  part  of  the  belly.  In  quadru- 
peds, with  but  few  exceptions,  this  is  the 
situation  of  the  mammas. 

In  virgin  mares  the  udder  is  so  small 
that  there  hardly  appears  to  be  any.  In 
mares  who  have  had  foals,  the  udder  re- 
mains prominent  or  pendulous,  and  has  a 
flabby  feel. 


Toward  the  latter  part  of  gestation,  this 
part  swells,  and  becomes  distinctly  visible. 
Within  a  few  days  of  foaling,  the  udder 
grows  turgid  with  milli ;  it  does  not,  how- 
ever, acquire  its  full  distention  until  the 
foal  has  drawn  it  for  a  few  days,  from 
which  time  it  maintains  its  volume,  with 
little  variation,  during  the  period  of  suck- 
ling. Soon  after  the  foal  begins  to  forsake 
the  teat,  the  secretion  of  milk  diminishes, 
and  is  followed  by  a  contraction  of  the 
bag,  which  goes  on  gradually,  until  it  has 
resumed  nearly,  or  quite,  its  former  flat- 
ness. 

The  interior  of  the  mammae  has  a  fight 
yellowish  aspect,  and  evidently  possesses  a 
lobulated  structure,  which  is  held  together 
by  a  fine  cellular  tissue,  interspersed  with 
granules  of  fat.  It  is  constituted  of  glan- 
dular masses,  irregular  in  magnitude  and 
form,  and  loosely  connected  one  with 
another,  each  of  which  masses  is  composed 
of  a  number  of  lobules,  closely  compacted 
and  united  together.  These  insulated  lob- 
ulous  portions  receive  small  arteries,  from 
which  the  milk  is  secreted.  The  former, 
by  repeatedly  conjoining  one  with  another, 
become  at  length  several  demonstrable 
canals,  radiating  from  every  part,  and  dilat- 
ing to  hold  the  milk. 

When  the  udder  becomes  charged  with 
milk,  it  flows  into  the  teat  and  distends  it. 
Suction  is  apparently  an  operation  purely 
mechanical.  The  teat  is  seized  and  closely 
compressed  by  the  lips  of  the  foal ;  and  the 
imbibing  effort  which  foUows  has  a  ten- 
dency to  produce  a  vacuum,  or  raise  the 
valve  at  the  upper  part  of  the  teat,  and  the 
milk  passes  from  the  reservoirs  into  the 
mouth. 


PHYSIOLOGICAL  CONSIDERATIONS. 


ON    THE    REPRODUCTION    OF    ORGANIZED 

BEINGS.* 

"  If  the  changes  which  living  beings  un- 
dergo during  the  period  of  their  existence, 
and  the  termination  of  that  existence  by 
the  separation  of  their  elements  at  a  period 
more  or  less  remote  from  their  first  combina- 
tion, be  regarded  as  distinguishing  them  in 
a  striking  and  evident  manner  from  the 
masses  of  inert  matter  which  surround  them, 
still  more  is  their  difference  manifested  in 
the  series  of  processes  which  constitute  the 
function  of  Reproduction.  A  very  unneces- 
sary degree  of  mystery  has  been  spread 
around  the  exercise  of  this  function,  not 
only  by  general  inquirers,  but  by  scientific 
physiologists.  It  has  been  regarded  as  a 
process  never  to  be  comprehended  by  man, 
of  which  the  nature  and  the  laws  are  alike 
inscrutable.  A  fair  comparison  of  it,  how- 
ever, with  other  functions,  will  show  that  it 
is  not  in  reality  less  comprehensible  or  more 
recondite  than  any  one  of  them; — that  our 
acquaintance  with  each  depends  upon  the 
facility  with  which  it  may  be  submitted  to 
investigation ; — and  that,  if  properly  in- 
quired into  by  an  extensive  survey  of  the 
animated  world,  the  real  character  of  the 
process,  its  conditions,  and  its  mode  of  oper- 
ation, may  be  understood  as  completely  as 
those  of  any  other  vital  phenomenon. 

"  It  may  be  considered  as  a  fundamental 
truth  of  Physiological  Science,  that  every 
living  organism  has  had  its  origin  in  a  pre- 
existing organism.  The  doctrine  of  '  spon- 
taneous generation,'  or  the  supposed  origina- 
tion of  organized  structures  de  novo  out  of 
assemblages  of  inorganic  particles,  although 
at  different  times  sustained  with  a  consider- 

*  Carpenter's  Physiology. 


able  show  of  argument,  based  on  a  specious 
array  of  facts,  cannot  now  be  said  to  have 
any  claim  whatever  to  be  received  as  even 
a  possible  hypothesis  ;  all  the  facts  on  which 
it  claimed  to  rest  having  either  been  them- 
selves disproved,  or  having  been  found  satis- 
factory explicable  on  the  general  principle 
omne  vivum  ex  ovo.  Thus,  the  appearance 
of  Animalcules  in  infusions  of  decaying 
organic  matter,  the  springing-up  of  Fungi 
in  spots  to  which  it  would  not  have  been 
supposed  that  their  germs  could  have  been 
conveyed,  the  occurrence  of  Entozoa  in  the 
bodies  of  various  animals  into  which  it 
seemed  almost  beyond  possibility  that  their 
eggs  could  have  been  introduced,  with 
other  facts  of  a  like  nature,  may  now  be 
accounted  for,  without  any  violation  of 
probability,  by  our  increased  knowledge  of 
the  mode  in  which  these  organisms  are  pro- 
pagated. Thus,  it  is  now  well  ascertained 
that  the  germs  of  Fungi  and  of  many  lands 
of  Animalcules  are  diffused  through  the 
atmosphere,  and  are  conveyed  by  its  move- 
ments in  every  direction ;  and  that,  if  to  de- 
composing substances  of  a  kind  that  would 
otherwise  have  been  most  abundantly  peo- 
pled by  these  organisms,  such  air  only  be 
allowed  to  have  access  as  has  been  deprived 
of  its  organic  germs  by  filtration  (so  to 
speak)  through  a  red-hot  tube  or  strong 
sulphuric  acid,  no  living  organisms  will 
make  their  appearance  in  them ;  whilst  in 
a  few  hours  after  the  exposure  of  the  very 
same  substances  to  ordinary  atmospheric 
air,  it  has  been  found  to  be  crowded  with 
life.*  And  when  it  is  borne  in  mind,  in  the 
case  of  the  Entozoa,  that  the  members  of 


*  See  the  experiments  of  Schuke,  in  the  "  Edinb.  New 
Phil.  Journal,"  1837,  p.  165. 

(128) 


ANATOMY  AND  PHYSIOLOGY  OF  THE  HORSE. 


129 


this  class  are  remarkable  for  the  immense 
number  of  eggs  which  most  of  them  pro- 
duce, for  the  metamorphoses  which  many 
of  them  are  known  to  undergo,  and  for  the 
varieties  of  form  under  which  there  is  reason 
to  suspect  that  the  same  germs  may  de- 
velop themselves,  it  becomes  obvious  that 
no  adequate  proof  has  yet  been  afforded 
that  they  have  been,  in  any  particular  case, 
otherwise  than  the  products  of  a  pre-existing 
living  organism.  This,  again,  is  the  con- 
clusion to  which  all  the  most  general  doc- 
trines of  Physiology  necessarily  conduct  us. 
For  it  is  most  certain  that  we  know  noth- 
ing of  Vital  Force,  save  as  manifested 
through  organized  structures ;  whilst,  on  the 
other  hand,  the  combination  of  inorganic 
matter  into  organized  structures  is  one  of 
the  most  characteristic  operations  of  vital 
force ;  hence  it  is  scarcely  conceivable  that 
any  operation  of  physical  forces  upon  inor- 
ganic matter  should  evolve  a  living  organ- 
ism. Nor  is  such  a  conception  more  feasi- 
ble, if  it  be  admitted  that  vital  force  stands 
in  such  a  relation  to  the  physical  forces, 
that  we  may  regard  the  former  as  a  mani- 
festation of  the  latter,  when  acting  through 
organized  structures ;  since  no  vital  force 
can  be  manifested  (according  to  this  view), 
and  no  organization  can  take  place,  except 
through  a  pre-existing  organism. 

"  It  may  be  further  considered  as  an  es- 
tablished physiological  truth,  that,  when 
placed  under  circumstances  favorable  to 
its  complete  evolution,  every  germ  will  de- 
velop itself  into  the  likeness  of  its  parent; 
drawing  into  itself,  and  appropriating  by 
its  own  assimilative  and  formative  opera- 
tions, the  nutrient  materials  supplied  to  it ; 
and  repeating  the  entire  series  of  phases 
through  which  its  parent  may  have  passed, 
however  multiform  these  may  be.*  Now 
the  germs  of  all  tribes  of  plants  and 
animals  whatever  bear  an  extremely  close 
relation  to  each  other  in  their  earliest  con- 
dition ;  so  that  there  is  no  appreciable  dis- 

*  The  apparent  exceptions  to  this  rule,  which  have  heen 
brought  together  under  the  collective  term,  "  Alternation  of 
Generations,"  will  be  presently  considered,  and  will  be 
shown  to  be  only  exceptional  when  misinterpreted. 
17 


tinction  amongst  them,  which  would  enable 
it  to  be  determined  whether  a  particular 
molecule  is  the  germ  of  a  Conferva  or  of 
an  Oak,  of  a  Zoophyte  or  of  a  Man.  But 
let  each  be  placed  in  the  conditions  it  re- 
quires ;  and  a.  gradual  evolution  of  the 
germ  into  a  complex  fabric  will  take  place, 
the  more  general  characters  of  the  new  or- 
ganism preceding  the  more  special^  as 
aheady  explained.  These  conditions  are 
not  different  in  kind  from  those  which  are 
essential  to  the  process  of  nutrition  in  the 
adult ;  for  they  consist,  on  the  one  hand,  in 
a  due  supply  of  aliment  in  the  condition 
in  which  it  can  be  appropriated;  and,  on 
the  other  hand,  in  the  operation  of  certain 
external  agencies,  especially  heat,  which 
seems  to  supply  the  force  requisite  for  the 
developmental  process.  Now,  although  we 
may  not  be  able  to  discern  any  such  osten- 
sible differences  in  the  germs  of  different 
orders  of  living  beings  as  can  enable  us  to 
discriminate  them  from  each  other,  yet,  see- 
ing so  marked  a  diversity  in  their  operations 
under  circumstances  essentially  the  same, 
we  cannot  do  otherwise  than  attribute  to 
them  distinct  properties ;  and  it  will  be  con- 
venient to  adopt  the  phrase  germinal  capa- 
city as  a  comprehensive  expression  of  that 
peculiar  endowment,  in  virtue  of  which 
each  gerii.  Jevelopes  itself  into  a  structure 
of  its  own  specific  type,  when  the  requisite 
forces  are  brought  to  bear  upon  it,  and  the 
requisite  materials  are  supplied  to  it.* 
Thus,  then,  every  act  of  development 
may  be  considered  as  due  to  the  force  sup- 
plied by  heat  or  some  other  physical  agency, 
which,  operating  through  the  organic  germ, 
exerts  itself  as  formative  power  ;  whilst  the 
mode  in  which  it  takes  effect  is  dependent 

*  This  tenn  is  preferred  to  that  of  "  germ-power  "  sug- 
gested by  Mr.  Paget,  because  the  latter  seems  to  imply 
that  the  force  of  development  exists  in  the  germ  itself. 
Now,  if  this  were  true,  not  only  must  the  whole  formative 
power  of  the  adult  have  been  possessed  by  its  first  cell- 
germ,  but  the  whole  formative  power  of  all  the  beings 
simultaneously  belonging  to  any  one  race,  must  have  been 
concentrated  in  the  first  cell-germ  of  their  original  proge- 
nitor. This  seems  a  reductio  ad  absurdum  of  any  such 
doctrine ;  and  we  are  driven  back  on  the  assumption 
(which  all  observation  confirms),  that  the /ore*  of  develop- 
ment is  derived  from  external  agencies. 


130 


ANATOMY  AND   PHYSIOLOGY  OF 


upon  the  properties  or  endowments  of  the 
substances  through  which  it  acts,  namely, 
the  germ  on  the  one  hand,  the  alimentary 
materials  on  the  other, — just  as  an  electric 
current,  transmitted  through  the  different 
nerves  of  sense,  produces  the  sensory  im- 
pressions which  are  characteristic  of  each 
respectively ;  or,  as  the  same  current  trans- 
mitted through  one  form  of  inorganic 
matter  produces  light  and  heat,  through 
another,  chemical  change,  or  through  an- 
other, magnetism. 

"  In  the  development  of  any  living  being, 
therefore,  from  its  primordial  germ,  we  have 
three  sets  of  conditions  to  study — namely, 
first,  the  physical  forces  which  are  in  opera- 
tion ;  second,  the  properties  of  the  germ, 
which  these  forces  call  inta  activity;  and 
third,  the  properties  of  the  alimentary  mate- 
rials which  are  incorporated  in  the  organism 
during  its  development.  There  is  evidence 
that  each  of  these  may  have  a  considerable 
influence  on  the  result ;  but  in  the  higher 
organisms  it  would  seem  that  the  second  is 
more  dominant  than  it  is  in  the  lower.  For 
among  many  of  the  lower  tribes,  both  of 
plants  and  animals,  there  is  reason  to  be- 
lieve that  the  range  of  departure  from  the 
characters  of  its  parent,  which  the  organism 
may  present,  is  considerably  greater  than 
that  of  the  higher ;  and  that  this  is  chiefly 
due  to  the  external  conditions  under  which 
it  has  been  developed.  The  forms  of  a 
number  of  species  of  the  lower  Fungi,  for 
example,  appear  to  be  in  a  great  part  de- 
pendent on  the  nature  of  their  aliment ;  so 
among  the  Entozoa,  there  seems  strong 
reason  to  believe  that. those  of  the  Cystic 
order  are  only  Cestoidea,  that  are  prevented 
by  the  circumstances  under  which  they  exist 
from  attaining  their  full  development ;  and 
the  production  of  a  fertile  'queen'  or  of  an 
imperfect  'worker,'  among  the  hive-bees, 
appears  to  be  entirely  determined  by  the 
food  with  which  the  larva  is  supplied.  No 
such  variations  have  been  observed  among 
the  higher  classes ;  in  which  it  would  seem 
as  if  the  form  attained  by  each  germ  is 
more  rigidly  determined  by  its  own  endow- 
ments ;   a  modification  in  the  other  con- 


ditions, which  in  the   lower  tribes  would 
considerably  affect  the  result,  being  in  them 
unproductive  of  any  corresponding  change. 
For,  if  such   modification   be  considerable, 
the  organism  is  unable  to  adapt  itself  to  it, 
and  consequently  cither  perishes  or  is  imper- 
fectly developed ;  whilst,  if  it  be  less  potent, 
it  produces  no  obvious  eftbct.     Thus,  a  de- 
ficiency of  food  in  the  growing  state  of  the 
higher  animal  will  necessarily  prevent  the 
attainment  of  the  fuU  size ;  but  it  will  not 
exert  that  influence  on  the  relative  develop- 
ment of  different  parts  that  it  does  among 
plants,  in  which  it  favors  the  production  of 
flowers  and  fruit  in  place  of  leaves,  or  that 
it  seems  to  exercise  in  several  parallel  cases 
among  animals.     So,  again,  a  deficiency  of 
heat  may  slightly  retard  the  development  of 
the  chick  ;  but,  if  the  egg  be  allowed  to  re- 
main long  without  the  requisite  warmth, 
the  embryo  dies,  instead  of  passing  into  a 
state  of  inactivity,  like  that  of  reptiles  or 
insects.     The  extent,  indeed,  to  which  these 
external  conditions  may  affect  the  develop- 
ment of  the  inferior  organisms,  must  not  be 
in  the   least  judged  of  by  that   to   which 
their  operation  is  restricted  in  the  higher ; 
and  it  is  probable  that  we  have  yet  much  to 
learn   on  the   subject.     At  present,  it  may 
be  stated  as   a  problem  for  determination, 
whether,  from  a  being  of  superior  organiza- 
zation,    loioer   forms    of    living    structure, 
capable   of    maintaining    an    independent 
existence,   and  of    propagating  their  kind, 
can  ever  originate,  by  an  imperfect  action 
of  its  formative  powers.     Various  morbid 
growths,  such  as  cancer  cells,  to  which  the 
higher    organisms    are    liable,    have   been 
looked  upon  in  this  light ;  these  have  cer- 
tainly   a    powerful    vitality    of   their   own, 
which  enables  them  to  increase  and  multi- 
ply at  the  expense  of  the  organism  which 
they  infest ;  and  they  have  also  an  energetic 
reproductive  power,  by  which  they  can  pro- 
pagate  their  kind,  so    as    to   transmit   the 
disease   to  other   organisms,  or   to   remote 
parts   of    the   same   organism  ;    but   such 
grow'ths  are  not  independent ;  they  cannot 
maintain   their   own    existence,   when   de- 
tached from  the  organism  in  which  they  are 


THE  HORSE. 


131 


developed;  and  they  have  not,  therefore, 
the  attribute  of  a  separate  individuality. 
Various  phenomena  hereafter  to  be  detailed, 
however,  respecting  the  '  gemmiparous ' 
production  of  living  beings,  when  taken  in 
connection  with  that  just  cited,  seem  to  ren- 
der it  by  no  means  impossible  that  the  in- 
dividualization may  be  more  complete  in 
other  cases,  so  that  independent  beings  of  a 
lower  type  may  possibly  originate  in  a  per- 
verted condition  of  the  formative  operations 
in  the  higher.  But  no  satisfactory  evidence 
has  ever  been  aftbrded  by  experience,  that 
such  '  equivocal  generation '  has  actually 
taken  place ;  and  its  possibility  is  here 
alluded  to  only  as  a  contingency  which  it  is 
right  to  keep  in  view.  That  no  higher  type 
has  ever  originated  through  an  advance  in 
developmental  power,  may  be  safely  as- 
serted ;  for,  although  various  instances  have 
been  brought  forward  to  justify  the  asser- 
tion that  such  is  possible,  yet  these  instances 
entirely  fail  to  establish  the  analogy  that  is 
sought  to  be  drawn  from  them.* 

*  Thus,  the  author  of  the  "  Vestiges  of  the  Natural 
History  of  Creation  "  refers  to  the  various  modifications 
which  have  taken  place  in  our  cultivated  Plants  and 
Domesticated  Animals,  in  proof  that  such  elevation  is 
possible ;  quite  overlooking  the  fact  that  these  external  in- 
fluences merely  modify  the  development,  without  elevating 
it,  and  that  these  races,  if  left  to  themselves,  speedily  revert 
to  their  common  specific  type.  And  he  adduces  the 
phenomena  of  metamorphosis — the  transformation  of 
the  worm-like  larva  into  an  insect,  and  of  a  fish-like 
tadpole  into  a  frog  —  as  giving  some  analogical  sanction 
to  the  same  doctrine ;  totally  overlooking  the  fact,  that 
these  transformations  are  only  part  of  the  ordinary  develop- 
mental process,  by  which  the  complete  form  of  the  species 
is  evolved,  instead  of  being  transitions  from  the  perfected 
type  of  one  class  to  the  perfected  type  of  one  above  it. 
So,  again,  he  quotes  the  transformation  of  the  worker- 
grub  of  the  hive-bee  into  the  fertile  queen,  as  an  example 
of  a  similar  advance ;  without  regarding  the  circumstance 
that  the  worker  is  pltysicaUy  higher  (according  to  human 
ideas,  at  least)  than  the  queen,  whose  Instincts  appear 
limited  to  the  performance  of  her  sexual  functions ;  and 
that  the  utmost  which  the  fact  is  capable  of  proving,  is, 
that  the  same  germ  may  be  developed  into  two  different 
forms,  according  to  the  circumstances  of  its  early  growth. 
It  must  always  be  borne  in  mind  that  the  character  of  a 
species,  to  be  complete,  should  include  all  its  forms,  per- 
fect and  imperfect,  modified  and  unmodified  ;  since  in  this 
mode  alone  can  that  "  capacity  for  variation "  be  deter- 
mined, which  is  so  remarkal)le  a  feature  in  many  cases, 
and  is  that  which  specially  distinguishes  the  races  of  plants 
and  animals  that  have  been  subjected  to  human  influence. 


"  The  development  power  which  each  germ 
possesses,  under  the  conditions  just  now 
detailed,  is  manifested,  not  merely  in  the 
first  evolution  of  the  germ  into  its  com- 
plete specific  type,  but  also  in  the  main- 
tenance of  its  perfect  form,  and,  within 
certain  limits,  by  the  reproduction  of  parts 
that  have  been  destroyed  by  injury  or  dis- 
ease. This  reproduction,  as  Mr.  Paget  has 
pointed  out,*  differs  from  the  ordinary  pro- 
cess of  nutrition  in  this,  —  that  '  in  grave 
injuries  and  diseases,  the  parts  that  might 
serve  as  models  for  the  new  materials  to  be 
assimilated  to,  or  as  tissue-germs  to  develop 
new  structures,  are  lost  or  spoiled  ;  and  yet 
the  effects  of  injury  and  disease  are  re- 
covered from,  and  the  right  specific  form 
and  composition  are  retained  ; '  —  and, 
again,  '  that  the  reproduced  parts  are 
formed,  not  according  to  any  present  model, 
but  according  to  the  appropriate  specific 
form,  and  often  with  a  more  strikingly  evi- 
dent design  towards  that  form,  as  an  end 
or  purpose,  than  we  can  discern  in  the  nat- 
ural construction  of  the  body.'  In  the  re- 
production of  the  leg  of  a  full-grown 
Salamander  after  amputation,  which  was 
observed  to  take  place  by  Spallanzani,  it  is 
clear  that,  whilst  the  process  was  from  the 
first  of  a  nature  essentially  similar  to  that 
by  which  its  original  development  took 
place,  it  tended  to  produce,  not  the  leg  of 
a  larva,  but  that  of  an  adult  animal.  Hence 
it  is  obvious  that,  through  the  whole  of  life, 
the  formative  processes  are  so  directed  as  to 
maintain  the  perfection  of  the  organism, 
by  keeping  it  up,  so  far  as  possible,  to  the 
model  or  archetype  that  is  proper  to  the 
epoch  of  its  life  which  it  has  attained. 
The  amount  of  this  regenerating  power, 
however,  varies  greatly  in  different  classes 
of  organized  beings,  and  at  different  stages 
of  the  existence  of  the  same  being ;  and,  as 
Mr.  Paget  has  pointed  out,t  it  seems  to 

In  no  instance  has  tliis  variation  tended  to  confuse  the 
limits  of  well-ascertained  species  ;  it  has  merely  increased 
our  acquaintance  with  the  number  of  diversified  forms  into 
which  the  same  germ  may  devclope  itself. 

*  "  Lectures  on  Reproduction  and  Eepair." 

t  Loc  cit. 


132 


ANATOMY   AND   PHYSIOLOGY   OF 


bear  an  inverse  ratio  to  the  degree  of  devel- 
opment which  has  previously  taken  place 
in  each  case.  Thus,  in  the  Hydra  and 
other  Zoophytes,  it  would  appear  (as  in 
Plants)  to  be  almost  unlimited  ;  for  the  de- 
velopment process  in  them  is  checked  at 
such  an  early  period,  that  both  the  form  of 
the  organism  and  the  structure  of  its  tissues 
retain  the  most  simple  type  ;  and  by  the 
subdivision  of  one  individual,  no  fewer 
than  fifty  were  produced  by  Trembly.  In 
this,  as  probably  in  all  the  cases  in  which 
new  indi\iduals  have  been  obtained  by 
artificial  subdivision,  there  is  some  natural 
tendency  to  their  production  by  the  vege- 
tative process  of  gemmation ;  but  tliis  does 
not  always  manifest  itself.  It  is  a  curious 
fact,  that  the  first  attempt  at  regeneration, 
in  some  of  these  cases,  is  not  always  com- 
plete ;  but  that  successive  efforts  are  made, 
each  of  which  approximates  more  and 
more  closely  to  the  perfect  type.  This  was 
well  seen  in  one  of  Sir  J.  G.  Dalyell's  ex- 
periments; for  he  observed  that,  having 
cloven  the  stem  of  a  Tubularia  (a  Hydroid 
Zoophyte),  after  the  natural  fall  of  its  head, 
an  imperfect  head  was  at  first  produced, 
which  soon  fell  off  and  was  succeeded  by 
another  more  fully  formed ;  this  in  its  turn 
was  succeeded  by  another ;  and  so  on,  until 
the  fifth  head  was  produced,  which  was  as 
complete  as  the  original. 

"  As  a  general  statement  of  the  amount 
of  this  regenerating  power,  which  exists  in 
most  of  the  different  classes  of  animals, 
has  been  already  given,  it  is  unnecessary 
here  to  do  more  than  allude  to  some  of 
those  facts  which  most  strongly  bear  out 
the  doctrine  just  laid  down.  Next  to 
Zoophytes,  there  are  no  animals  in  which 
the  regenerative  power  is  known  to  be  so 
strong  as  it  is  in  the  lower  Articulata  (as 
the  Cestoid  Entozoa,  and  the  inferior  An- 
nelida), and  in  the  Planaria,  which  may 
perhaps  be  regarded  as  rather  approximat- 
ing to  the  Molluscous  type ;  and  here,  again, 
we  see  that  a  low  grade  of  general  devel- 
opment is  favorable  to  its  exercise,  and  that 
the  spontaneous  multiplication  which  occa- 
sionally takes   place  in  these  animals  by 


fission  or  gemmation,  is  only  another  form 
of  the  same  process.  In  the  higher  forms 
of  both  these  sub-kingdoms,  as  we  no 
longer  meet  with  multiplication  by  gemma- 
tion, so  do  we  find  that  the  reparative  power 
is  much  more  limited ;  the  only  manifesta- 
tion of  it  among  the  fully-formed  Arrach- 
nida  and  Crustacea  being  the  reproduction 
of  limbs,  and  the  power  of  effecting  even 
this  being  usually  deficient  in  perfect  In- 
sects. The  inquiries  of  Mx.  Newport, 
however,  upon  the  reproductive  powers  of 
Myriapods  and  Insects,  in  different  stages 
of  their  development,*  confirm  the  general 
principle  already  stated ;  for  he  has  ascer- 
tained that  in  their  larval  condition,  Insects 
can  usually  reproduce  limbs  or  antennae ;  and 
that  Myriapods,  whose  highest  development 
scarcely  carries  them  beyond  the  larvae  of 
perfect  Insects,  can  regenerate  limbs  or  an- 
tennae, up  to  the  time  of  their  last  moult, 
when,  their  normal  development  being  com- 
pleted, their  regenerative  power  seems  en- 
tirely expended.  The  Phasmidce  and  some 
other  insects  of  the  order  Orthoptera  retain  a 
similar  degree  of  this  power  in  their  perfect 
state ;  but  these  are  remarkable  for  the  similar- 
ity of  their  larval  and  imago  states,  the  latter 
being  attained,  as  in  Arachnida,  by  a  direct 
course  of  development,  without  anything 
that  can  be  called  a  '  metamorphosis.'  Lit- 
tle is  known  of  the  regenerative  power  in 
the  higher  Mollusca;  but  it  has  been 
affirmed  that  the  head  of  the  Snail  may 
be  reproduced  after  being  cut  off,  provided 
the  cephalic  ganglion  be  not  injured,  and 
an  adequate  amount  of  heat  be  supphed. 
In  Vertebrata,  again,  it  is  observable  that 
the  greatest  reparative  power  is  found 
among  Batrachian  Reptiles,  whose  devel- 
opment is  altogether  lower,  and  whose  life 
is  altogether  more  vegetative,  than  that  of 
probably  any  other  group  in  this  sub-ldng- 
dom.  In  Fishes,  it  has  been  found  that 
portions  of  the  fins  which  have  been  lost 
by  disease  or  accident  are  the  only  parts 
that  are  reproduced.  But  in  the  Sala- 
mander, entire  new  legs,  with  perfect  bones, 
nerves,  muscles,  etc.,  are  reproduced  after 

*  "  Philoijophical  Transactions,"  1844. 


THE  HORSE. 


133 


loss  or  severe  injury  of  the  original  mem- 
bers ;  and  in  the  Triton  a  perfect  eye  has 
been  formed  to  replace  one  which  had  been 
removed.  In  the  true  Lizards^  an  imper- 
fect reproduction  of  the  tail  takes  place, 
when  a  part  of  it  has  been  broken  off;  but 
the  newly-developed  portion  contains  no 
perfect  vertebraB,  its  centre  being  occupied 
by  a  cartilaginous  column,  like  that  of  the 
lowest  Fishes.  In  the  warm-blooded  Ver- 
tebrata  generally,  as  in  Man,  the  power  of 
true  reproduction  after  loss  or  injury  seems 
limited,  as  Mr.  Paget  has  pointed  out,*  to 
three  classes  of  parts,  namely  :  (1.)  '  Those 
which  are  formed  entirely  by  nutritive  rep- 
etition, like  the  blood  and  epethelia,  their 
germs  being  continually  generated  de  novo 
in  the  ordinary  condition  of  the  body ;  (2.) 
Those  which  are  of  lowest  organization, 
and  (which  seems  of  more  importance)  of 
lowest  chemical  character,  as  the  gelatinous 
tissues,  the  areolar  and  tendinous,  and  the 
bones;  (3.)  Those  which  are  inserted  in 
other  tissues,  not  as  essential  to  their  struc- 
ture, but  as  accessories,  as  connecting  or 
incorporating  them  with  the  other  struc- 
tures of  vegetative  or  animal  life,  such  as 
nerve-fibres  and  blood-vessels.  With  these 
exceptions,  injuries  or  losses  are  capable  of 
no  more  than  repair,  in  its  more  limited 
sense ;  i.  e.,  in  the  place  of  what  is  lost, 
some  lowly  organized  tissue  is  formed, 
which  fiUs  up  the  breach,  and  suffices  for 
the  maintenance  of  a  less  perfect  life.' 
Yet,  restricted  as  this  power  is,  its  opera- 
tions are  frequently  most  remarkable ;  and 
are  in  no  instance,  perhaps,  more  strikingly 
displayed,  than  in  the  re-formation  of  a 
whole  bone,  when  the  original  one  has  been 
destroyed  by  disease.  The  new^  bony  mat- 
ter is  thrown  out,  sometimes  within,  and 
sometimes  around,  the  dead  shaft;  and 
when  the  latter  has  been  removed,  the  new 
structure  gradually  assumes  the  regular 
form,  and  all  the  attachments  of  muscles, 
ligaments,  etc.,  become  as  complete  as  be- 
fore. A  much  greater  variety  and  com- 
plexity   of    actions    are    involved    in   this 

*  "  Lectures  on  Reproduction  and  Repair." 


process,  than  in  the  reprocjuction  of  whole 
organs  in  the  simpler  animals  ;  though 
its  effects  do  not  appear  so  striking.  It 
would  seem  that  in  some  individuals  this 
regenerating  power  is  retained  to  a  greater 
degree  than  it  is  by  the  class  at  large  ;  *  and 
here  again  we  find,  that  in  the  early  period 
of  development  the  power  is  more  strongly 
exerted  than  in  the  adult  condition.  The 
most  remarkable  proof  of  its  persistence  even 
in  Man,  has  been  collected  by  Prof.  Simp- 
son; who  has  brought  together  numerous 
cases  in  which,  after  '  spontaneous  amputa- 
tion of  the  limbs  of  a  foetus  in  utero,'  occur- 
ring at  an  early  period  of  gestation,  there 
has  obviously  been  an  imperfect  effort  at 
the  re-formation  of  the  amputated  part 
from  the  stump.f  By  the  knowledge  of 
these  facts  and  principles,  we  seem  justi- 
fied in  the  surmise,  that  the  occm-rence 
of  supernumerary  or  multiple  parts  is 
not  always  due  (as  usually  supposed)  to 
the  'fusion'  of  two  germs,  but  that  it 
may  result  from  the  subdivision  of   one ; 

*  One  of  the  most  curious  and  well-authenticated  in- 
stances of  this  kind  is  related  by  Jlr.  White,  in  his  work 
on  tlie  "  Regeneration  of  Animal  and  Vegetable  Sub- 
stances," 1785,  p.  16.  "Some  years  ago,  I  delivered  a 
la'dy  of  rank  of  a  fine  boy,  who  had  two  thumbs  upon  one 
hand,  or  rather,  a  thumb  double  from  the  first  joint,  the 
otlier  one  less  than  the  other,  each  part  having  a  pei-fcct 
nail.  When  he  was  about  three  years  old,  I  was  desired 
to  take  oiF  the  lesser  one,  which  I  did ;  but  to  my  great 
astonishment  it  grew  again,  and  along  with  it  the  nail. 
The  family  aftei'n'ards  went  to  reside  in  London,  where 
his  father  showed  it  to  that  excellent  operator,  William 
Bromfield,  Esq.,  surgeon  to  the  Queen's  household  ;  who 
said,  he  supposed  Mr.  'WTiite,  being  afraid  of  damaging 
the  joint,  had  not  taken  it  wholly  out,  but  he  would  dis- 
sect it  out  entirely,  and  then  it  would  not  return.  He  ac- 
cordingly executed  the  plan  he  had  described,  with  great 
dexterity,  and  turned  the  ball  fiiirly  out  of  the  socket; 
not%vithstanding  this,  it  grew  again,  and  a  fresh  nail  was 
foi-med,  and  the  thumb  remained  in  this  state."  The 
Author  has  been  himself  assured  by  a  most  intelligent 
Surgeon,  that  he  was  cognizant  of  a  case  in  which 
the  whole  of  one  ramus  of  the  lower  jaw  had  been 
lost  by  disease  in  a  young  girl,  yet  the  jaw  had  been  com- 
pletely regenerated,  and  teeth  were  developed  and  occu- 
pied then-  normal  situations  in  it. 

t  These  cases  were  brought  by  Prof.  Simpson  before 
the  Physiological  Section  of  the  British  Association,  at 
its  meeting  in  Edinburgh,  August,  1850.  The  Author, 
having  had  the  opportunity  of  examining  Prof.  Simpson's 
preparations,  as  well  as  two  living  examples,  is  perfectly 
satisfied  as  to  the  fact. 


134 


ANATOMY   AND   PHYSIOLOGY   OF 


for,  if  it  be  supposed  that  this  subdivi- 
sion has  taken  place  when  the  develop- 
mental process  has  advanced  no  further 
than  in  a  Hydra  or  a  Planaria,  it  seems  by 
no  means  impossible  that  each  part  might, 
as  in  those  creatures,  advance  in  its  devel- 
opment up  to  the  attainment  of  its  com- 
plete form. 

"  There  are  many  tribes,  both  of  Plants 
and  Animals,  in  which  multiplication  is 
effected  not  only  artificially  but  sponta- 
7ieoi(slt/,  by  the  separation  of  parts,  which, 
though  developed  from  the  same  germ  in 
perfect  continuity  with  each  other,  are  capa- 
ble of  maintaining  an  independent  exist- 
ence, and  which,  when  thus  separated,  take 
rank  as  distinct  individuals.  This  process, 
which  is  obviously  to  be  regarded,  no  less 
than  the  preceding,  as  a  peculiar  manifes- 
tation of  the  ordinary  operations  of  Nu- 
trition, may  take  place  in  either  of  four 
different  modes  —  1.  In  the  lowest  Cellular 
Plants,  and  the  simplest  Protozoa,  every 
component  cell  of  the  aggregate  mass  that 
springs  from  a  single  germ,  being  capable 
of  existing  independently  of  the  rest,  may 
be  regarded  as  a  distinct  individual;  and 
thus  every  act  of  gi'owth  which  consists  in 
the  multiplication  of  cells,  makes  a  corre- 
sponding augmentation  in  the  number  of 
individuals.  2.  In  many  organisms  of  a 
somewhat  higher  type,  in  which  the  fabric 
of  each  complete  individual  is  made  up  of 
several  component  parts,  we  find  the  new 
growths  to  be  complete  repetitions  of  that 
from  which  they  are  put  forth ;  afid  thus 
the  composite  organism  presents  the  sem- 
blance of  a  collection  of  individuals  united 
together,  so  that  nothing  is  needed  but  the 
severance  of  the  connection,  to  resolve  it 
into  a  number  of  separate  individuals,  each 
perfect  in  itself.  The  most  characteristic 
example  of  this  is  presented  by  the  Hydra, 
which  is  continually  multiplying  itself  after 
this  fashion ;  for  the  buds  or  '  geramsB ' 
which  it  throws  off  are  not  merely  struc- 
turally but  functionally  complete  (being 
capable  of  seizing  and  digesting  their  own 
prey),  previously  to  their  detachment  from 
the  parent.     3.  In  by  far  the  larger  propor- 


tion of  cases,  on  the  other  hand,  the 
'  gemma '  does  not  possess  the  complete 
structure  of  the  parent,  at  the  time  of  its 
detachment,  but  is  endowed  with  the  ca- 
pacity for  developing  whatever  may  be 
deficient.  Thus,  the  bud  of  a  Phanero- 
gamic Plant  possesses  no  roots,  and  its 
capacity  for  independent  existence  depends 
upon  its  power  of  evolving  those  organs. 
On  the  other  hand,  the  'zoospore'  of  an 
Ulva  or  a  Conferva  is  nothing  else  than  a 
young  cell,  from  which  the  entire  organism 
is  to  be  evolved  after  it  has  been  set  free; 
and,  even  in  the  •  bulbels '  of  the  Mar- 
chantia,  the  advance  is  very  little  greater. 
The  '  bulbels '  of  certain  Phanerogamic 
plants,  however,  bear  more  resemblance  to 
ordinary  buds.  4.  In  the  preceding  cases, 
the  organism  which  is  developed  by  this 
process  resembles  that  from  which  it  has 
been  put  forth ;  but  there  are  many  cases 
in  which  the  offset  differs  in  a  marked  de- 
gree from  the  stock,  and  evolves  itself  into 
such  a  different  form  that  the  two  would 
not  be  supposed  to  have  any  mutual  rela- 
tion, if  their  affinity  were  not  proved  by  a 
knowledge  of  their  history.  Sometimes 
we  find  that  the  ne^v  individual  thus  bud- 
ded off  is  in  every  respect  as  complete  as 
that  from  which  it  proceeded,  though  de- 
veloped upon  a  different  type ;  but  in  other 
instances  it  is  made  up  of  little  else  than 
a  generative  apparatus,  provided  with  loco- 
motive instruments  to  cany  it  to  a  distance, 
its  nutritive  apparatus  being  very  imperfect. 
Of  the  first,  we  have  an  example  in  the 
development  of  Medusse  from  the  Hydroid 
Polypes ;  and  of  the  second  in  the  peculiar 
subdivision  of  certain  Annelida,  hereafter 
to  be  described.  Now  it  is  obvious  that,  in 
this  process,  no  agency  is  brought  into 
play  that  differs  in  any  essential  mode  from 
that  which  is  concerned  in  the  ordinary  nu- 
tritive operation.  The  multiplication  of 
individuals  is  performed  exactly  after  the 
same  fashion  as  the  extension  of  the  parent 
organism  ;  and  the  very  same  parts  may 
be  regarded  as  organs  belonging  to  it,  or  as 
new  individuals,  according  to  their  stage  of 
development,   and  the   relation   of  depen- 


THE  HORSE. 


135 


dence  which  they  still  hold  to  it.  The  es- 
sence of  this  operation  is  the  multiplication 
of  cells  by  continual  subdivision. 

"  We  have  now,  on  the  other  hand,  to  in- 
quire into  the  nature  of  the  true  Generative 
process,  by  which  the  original  germ  is  en- 
dowed   with  its    developmental   capacity ; 
and  this  we  shall  find  to  be  of  a  character 
precisely   the    opposite   of    the   preceding. 
For,    under    whatever    circumstances    the 
generative  process  is  performed,  it  appears 
essentially  to  consist  in  the  re-imion  of  the 
contents  of  two  cells*  of  which  the    germ, 
v»^hich   is   the    real    commencement   of    a 
'  new  generation,'  is  the  result.     This  pro- 
cess is  performed  under  the  three  following 
conditions:    1.  All  the  cells  of  the  entire 
aggregate,  produced  hy  the  previous  subdi- 
vision, may  be  capable  of  thus  uniting  with 
each  otiier  indiscriminately  ;  there  being  no 
indication  of  any  sexual  distinction.    This 
is  what  we    see    in    the    simplest  Cellular 
plants.     2.   All  the  component  cells  of  each 
organism   may,  in   like   manner,   pair  with 
other  cells,  to   produce   fertile  germs  ;  but 
there  are   differences    in   the  shares  which 
they  respectively  take  in  the  process,  which 
indicate  that  their  endowments  are  not  pre- 
cisely similar,  and  that  a  sexual  distinction 
exists  between  them,  notwithstanding  that 
this  is  not  indicated  by  any  obvious  struc- 
tural character.     This  condition  is  seen  in 
the  Zygnema  and  its  allies.     3.  The  gen- 
erative power  is  restrict3d  to  certain  cells, 
which  are   set  apart   from   the  rest  of  the 
fabric,  and  destined  to  this  purpose  alone ; 
and  the  endowments  of  the  two  sets  are  so 
far   different,   that   the   one    fm-nishes    the 
germ,  whilst  the  other  supplies  the  fertiliz- 
ing  influence ;   whence  the    one    set    have 
been  appropriately  designated  '  germ-cells ' 
and  the  other  '  sperm-cells.'     Such  is  the 
case  in  all  the  higher  Plants  among  which 
a  true  generative  apparatus  has  been  dis- 
covered ;  and  also  throughout  the  Animal 
lungdom. 

*  In  very  rare  instances,  it  is  the  re-union  of  the  two 
parts  of  the  contents  of  the  same  cell,  which  had  pre- 
viously tended  to  separate  from  each  other,  as  if  in  the 
process  of  subdivision. 


"  Thus,   then,   in   the   entire   process  in 
which  a  new  being   originates,  possessing 
lilce    structure    and    endowments    with    its 
parent,  two  distinct  classes  of  actions  par- 
ticipate,—  namely,  the  act  of  Generation^ 
by  which  the  Germ  is  produced ;   and  the 
act  of  Development.)  by  which  that  germ  is 
evolved  into  the  complete  organism.     The 
former  is  an  operation  altogether  sui generis  ; 
the  latter  is  only  a  peculiar  modification  of 
the    Nuti'itive    function;    yet  it  may   give 
oriofin,  as  we  have  seen,  to  new  individuals, 
by  the  separation  (natural   or   artificial)  of 
the  parts  which  are  capable  of  existing  as 
such.     Now,  between  these  two  operations 
there  would  seem  to  be  a  kind  of  antago- 
nism.     Whilst  every  act  of   Development 
tends  to  diminish  the  '  germinal  capacity,' 
the  act  of  Generation  reneivs  it ;  and  thus 
the  tree,  which    has  continued   to   extend 
itself    by   budding   until    its   vital    energy 
is    well-nigh    spent,   may  develop    flowers 
and  mature  seeds   from  which  a   vigorous 
progeny  shall  spring  up.     But  the  multipli- 
cation  of  individuals  does  not  directly  de- 
pend upon  the  act  of  generation  alone ;  it 
may  be  accomplished  by   the  detachment 
of  gemmce.,  whose  production  is    a   simple 
act  of   development;    and  the  individuals 
thus  produced  are  sometimes  similar,  some- 
times dissimilar,  to  the  beings   from  which 
they   sprang.     When    they    are    dissimilar, 
however,  the  original  type  is  always  repro- 
duced by  an  intervening  act  of  generation ; 
and  the  immediate  products  of  the  true  gen- 
erative  act  always  resemble   one   another. 
Hence   the  phrase,  '  alternation  of  genera- 
tions,'  can  only  be  legitimately  employed 
when  the  term  generation  is  used   to  desig- 
nate a  succession  of  individuals,  by  what- 
ever process  they  have  originated;  an  ap- 
plication of  it  which  cannot  but  lead  to  a 
complete  obliteration  of  the  essential  dis- 
tinction which  the  attempt  has  been   here 
made  to  draw  between  the   generative  act 
and  the  act  of  gemmation.     For  when  it  is 
said   that  '  generation   a  produces  genera- 
tion B,  which  is  dissimilar  to  itself,  whilst 
generation  b  produces  generation  c,  which 
is  dissimilar  to  itself,  but  which  returns  to 


136 


ANATOMY   AND    PHYSIOLOGY   OF 


the  form  of  generation  a,'  it  is  entirely  left 
out  of  consideration  that  generation  a  pro- 
duces (the  so-called)  generation  b  by  a 
process  of  gemmation ;  whilst  the  process 
by  which  generation  b  produces  generation 
0  is  one  of  true  generation.  So  generation 
c  developes  d  by  gemmation,  which  resem- 
bles B ;  and  d,  by  a  true  generative  act, 
produces  e,  which  resembles  a  and  c.  This 
distinction,  although  it  may  at  first  sight 
appear  merely  verbal,  will  yet  be  found  of 
fundamental  importance  in  the  appreciation 
of  the  trvie  relations  of  these  processes,  and 
of  their  resulting  products.  So,  in  the 
Author's  opinion,  the  application  of  the 
term  '  generation  '  to  the  entire  product  of 
the  development  of  any  germ  originating 


in  a  generative  act,  whether  that  product 
consist  of  a  single  individual,  or  of  a  suc- 
cession, will  be  found  much  more  appropri-  "^ 
ate,  and  more  conducive  to  the  end  in  view, 
than  the  indiscriminate  application  of  it  to 
each  succession,  whether  produced  by  gem- 
mation or  by  sexual  re-union.  It  is  of 
great  importance  to  the  due  comprehension 
of  certain  phenomena  of  Reproduction, 
which  will  come  under  consideration  in  the 
Animal  kingdom,  that  the  relations  of  the 
products  of  these  two  processes  should  be 
rightly  appreciated;  and  this  appreciation 
of  them  will,  it  is  believed,  be  best  gained 
by  a  careful  inquiry  into  the  phenomena 
of  Reproduction  in  the  Vegetable  king- 
dom." 


EXAMINATIONS  RESUMED. 


GLAXDULAR  APPARATUS. 

Q.  Describe  the  structure  of  a  glandular  body.  — A. 
It  consists  of  a  collection  of  tubes,  more  or  less  convo- 
luted, united  by  cellular  substance  into  masses  of  a 
rounded  form,  constituting  a  lobule ;  each  lobule  has 
a  separate  investment  of  membrane;  and  the  whole 
aggregate  of  lobules  is  furnished  with  a  general  mem- 
branous envelope  or  capsule.  Each  gland  presents  a 
complex  arrangement  of  numerous  arteries,  veins, 
nerves,  and  Ij-mphatics,  and  most  of  them  are  provided 
with  an  excretory  duct,  which  conducts  the  secretion 
prepared  in  the  gland. 

Q.  What  glands  are  supposed  to  be  destitvite  of  a 
secretory  duct?  —  A.  The  pineal  gland,  thjToid,  thy- 
mus, and  renal  capsules. 

Q.  AVhat  function  do  most  of  the  glands  perform  ?  — 
A.  Their  function  is  two-fold,  namely,  the  separation 
of  some  material  fi-om  the  circvdating  fluid,  which 
would  otherwise  prove  injurious  to  the  system,  and  the 
elaboration  of  a  product  destined  to  renovate  the  tis- 
sues. 

OF   THE  ABDOMEN. 

Q.  How  is  the  ca^•ity  of  the  abdomen  bounded?  — 
A.  Anteriorly,  by  the  diaphragm;  posteriorly,  by  the 
peh-is ;  superiorly,  by  a  portion  of  the  vertebra ;  infe- 
riorly  and  laterally,  by  abdominal  muscles. 

Q.  Into  how  many  regions  is  the  abdomen  divided  ? 
—  A.  Into  nine,  as  follows :  right  and  left  hypochon- 
driac; right  and  left  lumbar;  right  and  left  iliac;  epi- 
gastric, umbilical,  and  liipogastric. 

PERITONEUM. 

Q.  Why  is  the  peritoneum   called  "  serous   mem- 


brane?"—  A.  In  consequence  of  the  serous  or  watery 
fluid  wth  which  its  surface  is  constantly  moistened. 

Q.  What  is  the  structure  of  serous  membranes  ?  — 
A.  The  same  as  that  of  the  areolar  tissue,  ha\ing  a 
very  smooth  and  glistening  inner  sm-face,  which  is 
covered  with  a  layer  of  cells ;  constituting  a  distinct 
tissue,  termed  epithelium.  This  is  in  contact  with  the 
primary  membrane,  thus  isolating  it  from  the  tissues 
beneath.  Sub-adjacent  to  tliis  is  a  layer  of  condensed 
areolar  tissue,  wliich  constitutes  the  chief  thickness  of 
the  serous  membrane,  and  confers  upon  it  its  strength 
and  elasticity;  tliis  gradually  passes  into  that  baser 
variety,  by  which  the  membrane  is  attached  to  the  part 
it  lines,  and  which  is  commonly  known  as  the  sub- 
serous tissue.  A  fibrous  tissue  enters  into  the  compo- 
sition of  the  membrane  itself,  and  its  filaments  inter- 
lace in  a  beautiful  network,  wliich  confers  upon  it 
equal  elasticity  in  every  dii-ection. 

Q.  What  is  the  purpose  of  tins  membrane  ?  —  A. 
To  facilitate  the  movements  of  the  contained  organs, 
by  forming  smooth  surfaces  which  shall  freely  glide 
over  each  other. 

ST01L\CH. 

Q.  What  effect  does  the  gastric  fluid  have  upon  the 
food  ? —  A.  It  is  supposed  to  have  the  property  of  dis- 
sohing  the  albuminous  and  gelatmous  constituents  of 
the  food. 

Q.  What  is  the  real  solvent  of  the  gastric  fluid  ?  — 
A.  Either  hych-ochleric,  acetic,  or  lactic  acid. 

Q.  Is  not  the  solvent  action  of  the  gastric  fluid  aided 
by  some  mechanical  means  ?  —  A.  Yes.  By  the  move- 
ments of  the  walls  of  the  stomach,  wloich  ai-e  produced 
by  the  successive  contractions  and  relaxations  of  their 


THE   HORSE. 


137 


muscular  fibres,  the  contents  of  the  stomach  are  thus 
J  kept  m  a  state  of  constant  agitation,  wWch  is  considered 
pfavorable  to  their  chemical  solution. 

Q.  Does  absor2)tion  of  nutritious  matter  take  place 
in  the  stomach  ?  —  A.  Yes.  A  portion  of  the  nutri- 
tious matter  dissolved  by  the  gastric  fluid  is  at  once 
absorbed  into  the  blood-vessels  of  the  stomach,  and 
never  passes  into  the  intestinal  tube,  nor  into  the  special 
lacteal  system  of  vessels. 

Q.  What  term  is  appHed  to  the  food  after  its  reduc- 
tion, in  the  stomach,  to  a  puljjy  mass  ?  —  A.  Chyme. 

Q.  Gas  is  frequently  evolved  in  the  stomach  and 
intestines  during  digestion :  how  do  you  accomit  for 
this  ?  —  A.  It  is  owing  to  a  disturbed  or  morbid  condi- 
tion of  that  process,  and  by  no  means  a  necessary  at- 
tendant upon  healthy  digestion. 

Q.  Does  violent  exercise  immediately  after  a  foed 
tend  to  retard  the  formation  of  chyme  ?  —  A.  It  does. 
The  circumstances  most  favorable  to  perfect  digestion 
are,  a  short  period  of  rest,  followed  by  gentle  exercise. 

Q.  Does  any  portion  of  the  food  ever  pass  unchanged 
through  the  pylorus  along  with  the  chyme  P — A.  Yes. 
Whole  oats  are  frequently  found  in  the  horse's  excre- 
ment. 

INTESTINES. 

Q.  The  aUment  now  bemg  converted  into  chyme, 
and  havmg  passed  the  pylorus,  what  becomes  of  it  ? 
—  A.  It  enters  the  duodenum. 

Q.  Having  entered  the  duodenum,  with  what  does 
the  chyme  mingle  ?  —  A.  The  biliary  and  jjancreatic 
secretions. 

Q.  What  effect  do  they  have  on  the  gastric  secretion 
and  the  chyme  ?  —  A.  The  biliary  and  pancreatic  secre- 
tions are  supposed  to  contain  an  excess  of  alkaH ;  this 
neutrahzes  the  acid  of  the  gastric  juice,  so  that  there  is 
no  forther  solution  of  albuminous  compounds,  but  the 
conversion  of  starch  into  sugar,  which  was  interrupted 
in  the  stomach,  now  recommences. 

Q.  What  are  the  uses  of  the  bile  ?  —  A.  The  chief, 
uses  of  the  bile  appear  to  be  those  of  a  chemical  agent 
promoting  the  decomposition  of  the  chyme,  and  also 
stimulating  the  secretion  of  mucus,  and  the  peristaltic 
action  of  the  intestines.    * 

Q.  AVhat  effect  has  the  pancreatic  juice  on  chjme  or 
the  elements  of  digestion  ?  —  A.  It  forms  an  emulsion 
with  oil  and  fat. 

Q.  The  chyme,  havuig  been  acted  on  by  the  preced- 
ing secretions,  what  name  is  then  given  to  it  ?  —  A. 
Chyle. 

Q.  Describe  the  properties  of  chyle  ?  —  J..  If  chyle 
be  taken  from  the  thoracic  duct  of  an  animal  a  few 
hours  after  it  has  taken  food,  it  has  very  much  the 
appearance  of  cream,  being  a  thick  fluid  of  an  opaque 
white  color,  without  smell,  and  ha^ing  a  shghtly  acid 
taste,  accompanied  by  a  perceptible  sweetness.  It 
restores  the  blue  color  of  Htmus,  previously  reddened 
by  acetic  acid,  and  appears,  therefore,  to  contain  a  pre- 
ponderance of  alkah.     When  subjected  to  microscoijic 

examination,  chyle  is  found  to  contain  a  multitude  of 
18 


globules,  of  smaller  diameter  than  those  of  the  blood, 
and  corresponding  in  size  and  appearance  to  those  of 
milk.  In  about  ten  minutes  after  it  is  removed  from 
the  thoracic  duct,  it  coagulates  mto  a  stiff  jelly,  wliich 
in  the  course  of  twenty-fom-  hours  separates  into  two 
parts,  prouding  a  firm  and  contracted  coagulum,  sur- 
romided  by  a  transparent  colorless  fluid. 

Q.  What  are  the  principal  ingredients  of  chyle?  — 
A.  A  large  proportion  of  albumen,  a  smaller  one  of 
fibrin ;  a  fatty  substance  or  emvdsion,  which  gives  to 
chyle  the  appearance  of  milk  ;  and  several  salts,  such 
as  carbonate  of  potassa,  mm-iate  of  potassa,  and  pro- 
phospate  of  iron. 

Q.  What  change  does  the  chyle  undergo  in  its  pas- 
sage along  the  various  vessels  ?  —  A.  Its  resemblance 
to  blood  increases  in  each  of  the  successive  stages  of  its 
progress  towards  the  heart  and  Imigs. 

Q.  How  are  the  chemical  changes,  and  the  contents 
of  the  intestines  propelled  through  the  tract  of  the 
ahmentary  canal  ?  —  A.  By»the  peristaltic  action  of  the 
muscular  coat  of  the  same. 

Q.  What  becomes  of  the  chyle  after  it  has  been  pre- 
pared in  the  duodenum  and  fu'st  intestines  ?  —  A.  It 
is  received  by  absorption  into  the  lacteals,  and  by  them 
conveyed  to  the  thoracic  duct,  which  transmits  it  to 
large  veins  in  the  vicinity  of  the  heart.  (See  distribu- 
tion of  lymphatics.) 

Q.  What  do  you  understand  by  the  "  absorbent  sys- 
tem?"— A.  The  absorbent  system  of  vessels  consists 
of  two  princijDal  divisions,  wliich  may  be  compared  to 
two  sets  of  roots  jjroceeding  from  a  common  trunk ; 
one  of  these  commences  upon  the  walls  of  the  intes- 
tines, and  is  termed  the  "  lacteal "  system ;  whilst 
the  other  takes  its  origin  in  various  joarts  of  the  sub- 
stance of  the  organism  at  large,  esj^ecially  in  the  skin 
and  subcutaneous  textures,  and  is  known  as  the  "  lym- 
phatic "  system. 

Q.  Where  do  the  lacteals  most  numerously  abound  ? 

—  ^.  In  the  small  mtestines,  below  the  pomt  at  which 
the  Hver  and  pancreas  chscharge  their  secretions. 

Q.  Where  do  the  lacteals  commence  ?  —  A.  Near 
the  fi'ee  extremities  of  the  villi  of  the  intestines. 

Q.  In  what  way  do  they  commence  ?  —  A.  It  was 
formerly  supposed  that  they  commenced  by  orifices 
upon  the  internal  surface  of  the  intestine ;  but  Carpen- 
ter, and  other  physiologists,  contend  that  the  lacteal 
vessels  form  loops  by  anastomosis  Mith  each  other,  so 
that  they  have  no  free  extremity. 

Q.  What  are  the  functions  of  the  large  intestines  ? 

—  A.  They  are  engaged  m  the  conveyance  and  expul- 
sion of  feculent  matter,  and  there  are  certain  changes 
which  take  place  in  their  contents,  in  aid  of  the  object 
of  nutrition,  the  exact  nature  of  which  has  never  been 
clearly  determined.  Accorduig  to  the  best  authority,  it 
appears  that  some  important  changes  are  effected  in 
that  enlarged  portion  of  the  canal,  termed  coecum,  and 
wliich  has,  by  some,  been  regarded  as  a  kind  of  sup- 
plementary stomach,  in  which  fresh  chjTne  is  formed, 
and  fresh  nutriment  extracted  from  the  materials  that 
have  passed  tlu'ough  the  small  intestines.    The  large 


138 


ANATOMY   AND   PHYSIOLOGY   OP   THE   HORSE. 


intestines  also  extract  nutriment  from  their  contents, 
■which  is  proved  by  the  fact  that  nutritious  matter  in- 
jected into  tliem  has  been  knoMii  to  support  life  for  a 
certain  time. 

SPLEEN. 
Q.  "What  is  the  function  of  the  spleen?  —  A.  It 
serves  as  a  Icind  of  diverticulum,  to  relieve  the  vessels 
of  the  digestive  vescera  when  they  are  compressed  by 
undue  accummulation  of  the  contents  of  their  cavities, 
or  ■when  they  are  congested  by  obstruction  to  the  flow 
of  blood,  tlu'ough  the  liver  or  heart.  It  may  also  be 
considered  as  a  lymphatic  gland,  for,  in  some  instances 
in  wliich  animals  have  been  allowed  to  sm-nve  longest 
after  removal  of  the  spleen,  the  Ij-mphatic  glands  of 
the  ^icinity  have  been  found  greatly  enlarged  and  clus- 
tered together,  so  as  nearly  to  equal  the  origmal  spleen 
in  volume  ;  hence,  in  such  case  we  infer  that  its  func- 
tion must  be  similar  to  that  of  the  enlai-ged  IjTuphatic 
glands. 

LIVER. 

Q.  What  comprises  the  principal  bulk  of  the  liver  ? 
—  A.  It  is  made  up  of  a  vast  number  of  minute  lobules 
of  irregular  form,  but  about  the  average  size  of  a  mil- 
let seed ;  and  each  of  them  contains  the  elements  of 
which  the  entii-e  organ  is  composed,  ^■^z.,  a  plexus  of 
biliaiy  ducts  connected  M-ith  their  main  trmiks,  and  a 
mass  of  biliary  cells ;  each  of  -which  are  connected  in 
like  manner  with  the  three  blood-vessels  ■which  imite 
to  the  circulation  of  this  organ. 

Q.  What  are  the  vessels  of  the  Hver?  —  A.  The 
hepatic  artery,  vena  portae,  and  hepatic  veins,  to  ■which 
may  be  added  the  excretory  ducts  and  absorbents. 

Q.  Of  what  use  is  the  hepatic  artery  .f  —  A.  It  is  the 
nutrient  arteiy  of  the  liver. 

Q.  Of  what  use  is  the  vena  portae  ?  —  A.  It  acts  both 
as  a  vein  and  arterj' :  as  a  vein,  it  receives  the  blood 
from  most  of  abdominal  -riscera ;  as  an  arterj',  it  rami- 
fies through  the  Uver  for  the  secretion  of  bile. 

Q.  What  is  the  use  of  the  hepatic  veins  ?-—^.  They 
retm-n  blood  to  the  vena  cava. 

Q.  AMiat  is  the  function  of  the  liver  ?  —  A.  It  is  an 
organ  of  excretion,  designed  to  remove  from  the  ckcu- 
lating  fluid  that  portion  of  the  products  of  disintegra- 
tion, of  which  the  principal  component  of  the  lu'inary 
is  the  largest. 


Q.  Into  what  substance  is  the  greater  part  of  the 
excrcmentitious  matter  converted  ?  — A.  Biline. 

KIDNEYS. 

Q.  T^^lat  is  the  cmbryotic  condition  of  the  kidneys  ? 
A.  The  kidneys  are  preceded  in  the  embryo  by  a  sub- 
stance first  noticed  by  Wolff",  and  called  after  him  the 
Wolffian  bodies,"  or  false  Iddneys,  which  originally  ex- 
tend along  the  spme  from  the  heart  to  the  end  of  the 
intestines;  but  they  afterwards  become  shorter,  and 
after  a  time  diminish  by  absorjition,  and  wholly  dis- 
ajipear. 

Q.  What  is  the  function  of  the  kidneys  ?  —  A.  Their 
principal  function  is  to  separate  from  the  blood  certain 
matters  which  would  be  injurious  to  it  if  retained. 

Q.  What  does  the  secretory  surface  of  the  kidneys 
consist  of?  —  A.  It  is  composed  of  epithelial  cells 
wliich  line  the  tubidi  m'inifera,  which  draw  the  peculiar 
elements  of  the  m'inary  excretion  fr-om  the  vascular 
plexus  which  surrounds  the  exterior  of  the  tubes,  car- 
rjing  oS"  the  same  to  their  terminations  in  the  ureter. 

Q.  AVhat  other  arrangement  is  provided  "nithin  the 
kidneys  for  the  elimination  of  the  superfluous  fluid  of 
the  blood?  —  A.  A  process  of  transudation  takes  place 
by  the  function  of  malpighian  bodies,  whose  thin-walled 
capillaries  allow  the  transudation  of  water  to  take 
place,  under  a  certain  pressm-e,  into  the  tubuli  urinifera. 

SUPRA-EENAL  CAPSULES. 

Q.  What  is  the  function  of  the  supra-renal  cap- 
sules ?  —  A.  Then-  function  has  hitherto  been  involved 
in  obscurity,  and  was  supposed  to  be  identical  ■with 
other  glands  destitute  of  ducts  or  outlets ;  but,  lately, 
M.  Broivn  Seguard  has  demonstrated  that  they  play 
a  very  important  part  in  the  nervous  system  of  the 
horse. 

VASA  DEFEEENTM.. 

Q.  What  is  the  function  of  the  vas  deferens  ?  —  A. 
It  is  the  excretory  duct  of  the  testicle,  and  conveys  the 
semen  to  the  vesiculae  seminales. 

The  author,  instead  of  introducing  examinations  on 
tlie  reproductive  organs,  has  thought  it  best  to  substi- 
tute the  opinions  of  that  eminent  phyisologist,  Dr. 
Cai'penter ;  and  therefore  the  reader's  attention  is  now 
directed  to  "  Physiological  considerations  on  the  re- 
production of  organized  beings.^' 


REMARKS  AND  EXAMINATIONS  ON  THE  EYE. 


The  parts  which  compose  the  eye  are 
divided  into  external  and  internal.  The 
external  parts  are  :  First,  the  eyelashes,  or 
cilia,  which,  in  the  horse,  can  scarcely  be 
reckoned  more  than  one,  there  being  very 
few  hairs  in  the  under  eyelid.  Secondly, 
the  eyelids,  or  palpebrse,  upper  and  under : 
where  they  join  outwardly,  it  is  termed  the 
external  canthus,  and  inwardly  toward  the 
nose,  the  internal  canthus :  they  cover  and 
defend  the  eyes.  The  cartilaginous  margin 
or  rim  of  the  eyelid,  from  which  the  eye- 
lashes proceed,  is  named  tarsus.  In  the 
tarsus  and  internal  sm-face  of  the  eyelid 
there  are  small  glands,  which  secrete  a  fluid, 
to  prevent  friction  of  the  eye  and  its  lids, 
and  facilitate  motion.  Thirdly,  the  lachry- 
mal gland,  which  is  placed  on  the  upper  part 
of  the  eyelid  toward  the  external  canthus ; 
from  this  gland  the  tears  are  secreted,  and 
conveyed  to  the  inner  surface  of  the  upper 
eyelid  by  several  minute  ducts,  or  canals, 
named  lachrymal  ducts.  There  is  another 
small  body,  having  a  glandular  appearance, 
in  the  inner  corner  of  the  eye ;  on  each  side 
of  which  there  are  smaU  orifices  which  are 
called  puncta  lachrymalia:  these  are  the 
mouths  or  openings  of  two  small  canals, 
which,  joining  together,  form  a  membranous 
tube ;  and  this,  passing  through  a  small  open- 
ing in  the  bone,  extends  to  the  lower  part 
of  the  nostril,  where  its  termination  may  be 
distinctly  seen  in  the  horse.  As  the  lachry- 
mal gland  is  constantly  forming  tears,  it 
must  be  obvious  that  some  contrivance  is 
necessary  to  convey  them  off,  and  prevent 
them  flowing  over  the  cheek :  this  purpose 
is  answered  by  the  canal  just  described. 

When  any  irritating  matter  is  applied  to 
the  eye,  the  tears  are  formed  too  abundantly 
to  be  carried  off  in  this  way;  they  then 
flow  over  the  cheek.     In  the  human  eye, 


the  puncta  lachrymalia  terminate  in  a  small 
sac,  from  which  the  lachrymal  duct  proceeds : 
this  is  not  the  case  in  the  horse.  In  the 
inner  corner  of  the  horse's  eye  is  placed  a 
body  commonly  termed  the  haw,  no  resem- 
blance to  which  is  to  be  found  in  the  hu- 
man eye.  The  horse  has  the  power,  by 
means  of  the  muscles  of  the  eye,  to  bring 
the  haw  completely  over  its  surface ;  it 
serves,  therefore,  as  a  second  eyelid,  and 
effectually  wipes  off  any  dust,  hay,  or  seeds, 
or  other  matter  which  may  have  fallen  upon 
the  eye.  The  conjunctive  membrane,  or 
tunica  conjunctiva,  lines  the  inner  surface 
of  the  eyelids,  and  covers  the  white  part  of 
the  globe  of  the  eye.  This  membrane  has 
numerous  blood-vessels,  which  are  conspicu- 
ous when  it  is  inflamed.  The  bulb  or  globe 
of  the  eye  is  composed  of  several  coats  and 
humors.  The  transparent  cornea,  which, 
in  the  horse,  forms  the  front  part  of  the  eye, 
comprehends  a  larger  part  of  the  globe 
than  in  the  human  subject ;  on  removing 
this  cornea,  a  fluid,  which  is  named  the 
aqueous  humor,  escapes,  and  the  iris  ap- 
pears. The  iris  is  a  muscular  curtain, 
having  a  hole  in  the  centre,  which  is  termed 
the  pupil.  This  divides  the  fore  part  of  the 
eye  into  two  parts,  named  chambers,  which 
are  occupied  by  the  aqueous  humor.  The 
pupU  is  of  a  dark  bluish  cast ;  is  of  an  oval, 
or  rather  of  an  oblong,  form.  The  iris  regu- 
lates the  quantity  of  light  that  is  required 
to  pass  through  the  pupil.  For  this  purpose, 
it  is  composed  of  two  sets  of  muscular 
fibres :  by  means  of  one  the  pupil  is  en- 
larged, and  by  the  other  it  is  diminished. 
Thus,  if  the  pupil  is  first  examined  in  the 
stable,  where  there  is  a  moderate  light,  and 
immediately  after  in  the  sunshine,  it  will  be 
found  quite  altered;  being  so  small,  in  a 
strong  light,  as  to  be  nearly  closed.     On  re- 


140 


ANATOMY  AND   PHYSIOLOGY  OP 


moving  the  iris,  the  second  humor,  or  crys- 
talline lens,  appears :  this  is  retained  in  its 
situation  by  a  transparent  membrane,  named 
its  capsule,  betvveen  which  and  the  lens  is  a 
minute  quantity  of  fluid.  The  third  humor 
of  the  eye  is  the  vitreous.  This  humor  is  not 
contained  in  one  general  sac,  but  in  numer- 
ous minute  and  perfectly  transparent  cells, 
and  resembles  pm-e  water  :  this  humor 
serves  to  produce  a  small  degree  of  refrac- 
tion in  the  rays  of  light,  and  occupies  and 
distends  all  the  posterior  part  of  the  globe 
of  the  eye.  The  next  coat  to  the  conjunctive 
is  the  sclerotica,  or  white  of  the  eye,  a 
strong,  thick  membrane,  which  extends 
from  the  transparent  cornea  to  the  optic 
nerve.  The  next  coat  to  the  sclerotic  is  the 
choroid.  This  is  a  delicate  and  very  vascu- 
lar membrane.  In  the  human  eye  it  appears 
of  a  black  color,  and  it  is  this  which  causes 
the  pupil  of  the  human  eye  to  appear  black ; 
but  the  choroid  coat  of  the  horse's  eye  is 
variegated  in  color ;  in  some  parts  black,  in 
others  blue,  and  in  others  green.  The  next 
coat  is  the  retina :  this  is  a  delicate  expan- 
sion of  the  optic  nerve  over  the  choroid 
coat,  which  it  accompanies  to  the  margin 
of  the  crystalline  lens,  and  there  terminates. 
The  use  of  the  retina  is  to  receive  certain 
impressions  made  by  the  light  reflected  from 
objects,  so  as  to  produce  in  the  mind  an 
idea  of  their  figure  and  color;  the  optic 
nerve  being  the  medium  of  communication 
between  the  retina  and  brain.  From  the 
above  explanation  of  the  mechanism  of  the 
eye,  it  will  readily  appear  that  many  cir- 


cumstances may  occur  to  render  vision  im- 
perfect, or  to  destroy  it  altogether.  If  the 
transparent  cornea,  for  example,  became 
white,  light  could  not  pass  through  it,  and 
the  animal  would  be  blind,  however  perfect 
the  other  parts  of  the  eye  might  be.  The 
cornea  may  be  either  too  convex  or  too  flat; 
in  the  former  case,  causing  the  animal  to  be 
near-sighted ;  in  the  latter,  producing  an  in- 
distinctness of  vision  with  respect  to  objects 
that  are  near.  The  iris  may,  in  consequence 
of  disease,  become  fixed,  or  lose  its  power 
of  motion  ;  in  which  case,  the  pupil  would 
be  always  of  the  same  size,  and  the  animal 
would  not  have  the  power  of  adapting  it 
to  the  various  distances  or  objects ;  or,  as 
sometimes  happens,  the  pupil  may  become 
quite  closed,  by  which  light  would  be  per- 
fectly excluded  from  the  retina.  Supposing 
the  cornea  and  iris  to  be  healthy,  the  crys- 
talline lens,  or  its  capsule,  may  become 
opaque,  and  thereby  cause  total  blindness. 
But  in  this  part,  as  in  the  cornea,  we  meet 
with  different  degrees  of  opacity :  some- 
times it  is  very  slight,  the  pupil  appearing 
of  a  lighter  color,  and  unusually  large :  in 
this  state,  the  pupil  is  said  to  look  duU  or 
muddy,  which  causes  the  horse  to  start ; 
but  when  the  opacity  is  complete,  it  consti- 
tutes the  disease  termed  cataract.  There 
is  another  disease,  to  which  the  reader's  at- 
tention is  caUed ;  it  is  named  gutta  serena, 
or  amaurosis.  This  disease  is  known  by 
the  pupil  being  unusually  large  or  open, 
and  by  its  continuing  so  when  the  eye  is 
exposed  to  a  strong  light. 


EXA3IINATI0NS  OF  THE  ORGANS  OF   SIGHT  AND  THEHl  APPENDAGES. 


Q.  Where  are  the  eyes  located? — A.  Within  the 
orbits. 

Q.  By  what  foraminae  is  each  orbit  perforated?  —  A. 
By  the  optic  forapien. 

Q.  From  whence  is  the  lining  membrane  of  the  orbit 
derived  ?  —  A.  From  the  dura  mater  and  periosteum, 

Q.  Enumerate  the  appendages  of  the  eye.  —  A.  The 
eycUds,  eyelashes,  muscles  of  the  eyeUds,  tarsal  carti- 
lages, meibomian  glands,  tunica  conjunctiva,  membrana 
nictitans,  lachrjTnal  gland,  puncta  lachrjinaUa,  lachi-y- 
mal  sac,  ductus  ad  nasum,  and  the  muscles  of  the  eye- 
ball. 


EYELIDS. 

Q.  What  parts  do  the  eyelids  occujjy  ?  —  ^I,  The  cir- 
cumference of  the  orbits  and  front  of  the  eyeball. 

Q.  What  are  the  eyehds  composed  of?  —  ^.  In  com- 
position they  are  cuticular,  muscular,  cartilaginous,  and 
membranous ;  also  glandular,  vascular,  and  nervous. 

Q.  What  muscle  enters  into  the  composition  of  the 
eye  ?  —  A.  The  orbicularis  palpebrarum. 

Q.  How  are  the  Uds  separated  ?  —  A.  By  a  transverse 
fissure,  bounded  by  the  angles  or  canthi  of  the  eye. 

Q.  What  is.  attached  to  the  superior  or  temporal 
angle?  —  A.  The  tarsal  ligament. 


EXPLANATION   OF   FIGURE  XIV. 


HIND  EXTREMITIES. 

m'.  Tensor  vagina. 

n\    Rectus. 

o'.    Vastus  externus. 

q\    Flexor  metatarsi. 

r\  r.  Gastrocnemius  intemus. 

s'.  "  externus. 

t'.    Flexor  pedis  accessorius. 

u\    Insertion  of  the  gastrocnemius. 

t)'.    Flexor  metatarsi. 

a;'.    Extensor  pedis. 

y.  y\  Extensoi's. 

u.v.  Tendo  perforans  et  perforatus. 

K'.  K\  Abductors  tibialis. 

J\  J\  Triceps. 

V.  V.  Adductors. 

^.  Hoof. 

5,  5.     Saphena  vein. 

8.    Bifui-cation  of  the  suspensory  ligament. 

r'.    (0£F-hiiid  leg.)     Peroneus. 

z.     Suspensory  ligament. 

POEE  EXTREMITIES. 

J".  Pectoralis  magnus. 
to",  n".  Triceps  extensor  brachii. 
o".  Pectoralis  transversalis. 
p".  p".  Flexor  metacarpi  externus. 
g".  "  "  medius. 

r".  "  "  internus. 

s".   Extensor  metacarpi  magnus. 

m".  (At  the  upper  part  of  the  figure.)     Levator  humeri. 

u".  m".  «".  u".  V.  (Beneath  the  olecranon  and  carpus.)     Flexors  perforans  and  per- 
foratus. 
x".  Extensor  pedis. 
?/".  y.  Extensor  suffraginis. 
z".  Suspensory  Hgament. 
Sf.  The  hoof. 

4.   Subcutaneous  thoracic  vein. 
6.  Radial  vein. 
8.   Bifurcation  of  the  suspensory  ligament. 


142 


ANATOMY   AND   PHYSIOLOGY   OF 


being  coated  it  detains  any  small  foreign  bodies  that 
may  float  in  the  lachr}Tnal  secretion ;  it  also  directs 
the  latter  fluid  into  the  puncta. 

LACHRYMAL  PLTsXTA  AXD  CONDUITS. 

Q.  "\Miat  are  the  pimcta  lachrj-malia  ?  —  A.  Two  small 
orifices  situated  on  the  inward  margins  of  the  two  lids  — 
superior  and  inferior  —  near  the  radix  of  the  caruncle. 

Q.  What  do  the  puncta  terminate  in?  —  A.  The 
lachrj-mal  conduits. 

Q.  AMiat  is  their  situation?  —  A.  Withm  the  sub- 
stance of  the  eyeHds. 

Q.  How  are  conduits  formed  ?  — A.  A  minute  carti- 
laginous circle  surrounds  them,  and  they  are  Hned  by 
conjunctival  membrane. 

Q.  What  do  the  conduits  terminate  in?  —  A.  The 
lachrjmal  sac. 

LACHRYMAL    SAC. 

Q.  Where  is  the  lacluymal  sac  situated  ?  —  A.  With- 
in the  depression  which  leads  into  the  channel  of  the 
lachr^-mal  bone,  beliind  and  below  the  small  eminence 
upon  the  orbital  ridge  of  that  bone. 

Q.  Describe  tlie  sac  and  its  connections  ?  —  A.  It  is 
an  oblong  membranous  bag;  its  front  is  crossed  by 
fibres  of  the  orbicularis ;  it  has  also  a  connection  with 
the  tendon  of  that  muscle.  The  j^osterior  part  of  the 
sac  adheres  fii-mly  to  the  lachrymal  bone.  It  is  com- 
posed of  a  dense,  white,  fibrous  membrane,  fiimished 
with  a  lining  from  the  conjunctivia. 

Q.  By  what  is  this  sac  perforated  ?  —  A.  By  the 
lachrjmal  conduits. 

Q.  What  does  it  open  into  ?  —  A.  Into  the  ductus  ad 
nasiun. 

Q.  What  is  the  function  of  this  sac?  —  A.  It  is  a 
reservoir  into  which  the  tears  flow  from  the  lachrymal 
conduits,  and  fi'om  thence  pass  into  the  ductus  ad 
nasum. 

DUCTUS  AD  NASUM. 

Q.  "WHiat  is  the  ductus  ad  nasum?  —  A.  It  is  a  long 
membranous  canal,  commencmg  at  the  contracted  por- 
tion of  the  lachi-ymal  sac,  and  rumiing  with  the  groove 
through  the  lachrj-mal  bone ;  then  along  a  canal  in  the 
superior  maxillary  bone,  between  it  and  the  anterior 
turbinated  bone ;  terminating  at  the  imier  and  inferior 
part  of  the  nostril. 

Q.  What  is  the  organization  of  the  ductus  ?  —  A.  It 
appears  to  be  a  continuation  of  the  membrane  com- 
posing the  lachrymal  sac,  Avhich  is  strengthened  by  a 
fibrous  sheath ;  its  internal  surface  is  probably  mucous, 
which  protects  it  from  the  action  of  the  tears,  or 
lachrjTnal  secretion. 

Q.  Describe  the  course  of  the  tears,  or  lachrj-mal 
secretion  ?  —  A.  They  are  secreted  by  the  lachi-ymal 
gland,  and  ai-e  pom-ed  by  its  excretory  ducts  over  the 
sm'face  of  the  eyeball ;  the  puncta  lachrj-malia  absorb 
them ;  they  are  then  conveyed  by  the  lachrjuial  ducts 
to  the  lachrjTnal  sac ;  and  through  the  ductus  ad  nasiun 
pass  into  the  nostril. 


THE  EYEBALL  AND  ITS  COATS. 

Q.  What  is  the  form  of  the  globe  of  the  eye?  —  A. 
Nearly  of  a  spherical  figure. 

Q.  Of  what  is  the  globe  of  the  eye  composed? — A. 
Of  membranes,  or  coats,  filled  with  humoi's  or  fluids, 
which  preserve  its  form. 

Q.  How  many  coats  has  the  ej-e  ?  —  A.  Five :  the 
sclerotic,  choroid,  retina,  cornea,  and  iris. 

Q.  Does  not  the  tunica  conjuncti\ia  enter  into  the 
com  j^osition  of  the  membranes  of  the  eye?  —  A.  Yes: 
it  may  be  considered  as  common  to  both. 

Q.  Where  does  it  adhere  most  closely?  —  A.  Over 
the  cornea. 

SCLEROTIC   COAT. 

Q.  What  is  the  use  of  the  sclerotica  ?  —  A.  It  bomids 
the  form  of  the  eye,  protects  and  supports  the  parts 
within. 

Q.  What  are  its  perceivable  boundaries  ?  —  A.  It  ex- 
tends from  the  optic  nerve  to  the  cornea. 

Q.  What  is  inserted  into  it  posteriorly?  —  A.  The 
fleshy  part  of  the  retractor  muscle. 

Q.  What  is  inserted  into  its  anterior  margins  ?  —  A. 
The  tendons  of  the  four*  recti. 

CORNEA. 

Q.  What  is  the  comea  ?  —  A.  The  transparent,  ante- 
rior part  of  the  globe  of  the  eye. 

Q.  How  does  its  form  compare  with  the  sclerotica  ?  — 
P.  It  is  more  convex. 

Q.  What  covers  its  convex  surface  ?  —  A.  The  con- 
jmicti^da. 

Q.  What  is  its  structure?  —  A.  Laminated. 

IRIS. 

Q.  What  is  the  iris  ?  — A .  It  is  a  circular  membrane, 
with  an  irregular  central  ca^•ity,  in  the  anterior  chamber 
of  the  eye. 

Q.  What  is  its  central  perforation  called  ?  —  A.  The 
pupil. 

Q.  How  is  the  periphery  of  the  pupil  bounded  ?  —  A. 
By  several  dark,  colored,  glandular  bodies,  termed  cor- 
pora nigra. 

Q.  What  is  the  use  of  the  iris?  —  A.  By  contracting 
it  excludes  all  superfluous  rays  of  light,  and  by  expand- 
mg  admits  tlirough  the  pupil  all  that  pass  through  the 
cornea. 

Q.  What  is  the  structure  of  the  iris?  —  A.  It  is  a 
fibrous  membrane,  divisable  into  two  layers,  provided 
with  blood-vessels  and  nerves. 

CHOROID   COAT. 

Q.  What  is  the  choroid  coat  ?  —  yl.  It  is  a  dark- 
colored  membrane  of  dehcate  textm-c,  located  immedi- 
ately beneath  the  sclerotica. 

Q.  What  are  its  boundaries?  —  A.  It  extends  from 
around  the  termination  of  the  optic  nerve  as  far  for- 
ward as  the  edge  of  the  cornea,  and  ends  in  the  ciliary 
circle. 


THE   HOESE. 


143 


Q.  How  is  the  choroid  coat  connected  with  the 
sclerotica?  —  A.  By  cellular  membrane. 

Q.  What  is  remarkable  at  its  outer  edge  ?  —  A.  It  is 
thrown  into  folds,  called  cUiary  circle  and  processes. 

Q.  What  is  the  color  of  the  choroides  ?  —  A.  Extern- 
ally, its  whole  surface  is  black ;  internally,  the  anterior 
parts  are  black,  and  the  jDOsterior  half  is  of  a  brilliant 
variegated  green. 

Q.  AVhat  is  the  black  part  termed  ? — A.  Pigmentum 
nigrum. 

Q.  What  name  is  given  to  the  variegated  part  ?  —  A. 
Tapetum  lucidmn. 

Q.  What  difference  do  we  observe  in  the  pigment  of 
the  choroid  surfaces  ?  —  A.  The  imier  layer  is  thicker 
and  more  consistent  than  that  found  on  the  outer 
sm-face. 

RETINA. 

Q.  What  is  the  retina  ?  — A.  It  is  the  thii-d  or  mner- 
most  tunic  of  the  eye.  It  cannot,  however,  be  con- 
sidered as  a  tunic,  for  it  pervades  the  interior  of  the 
globular  expansion  without  contracting  any  adhesions 
until  it  has  reached  the  corpus  cihare. 

Q.  How  is  the  retina  fonned  ?  —  A.  The  optic  nerve, 
having  reached  the  inner  and  inferior  part  of  the  globe 
of  the  eye,  enters  the  sclerotic  and  choroid  coats,  and 
in  its  jDassage  through  them  its  diameter  contracts; 
ha^•ing  arrived  at  the  inner  part  of  the  globe,  the  nerve 
forms  an  eminence,  from  the  circumference  of  which 
issues  radiating  fibres  which  form  the  retina, 

Q.  How  is  the  retina  sustained  in  this  state  of  globu- 
lar expansion  ?  —  A.  By  the  humors  of  the  eye,  which 
keep  it  in  contact  ■nith  the  choroides. 

Q.  The  retina  ha^g  radiated  on  the  interior  of  the 
globe,  where  is  it  inserted  ?  —  A.  Lito  the  corpus  cihare. 

HUMORS  OF  THE  EYE. 

Q.  Of  how  many  humors  does  the  eye  consist,  and 
what  are  their  names? — A.  Of  three;  they  are  called 
aq^ueous,  crystalline,  and  vitreous  humors. 


Q.  What  parts  of  the  eye  do  they  occupy  ?  —  A. 
They  occupy  m  succession  the  spaces  termed  anterior, 
middle,  and  posterior  chambers  of  the  eye. 

AQUEOUS  HUMOR. 

Q.  What  is  the  use  of  the  aqueous  humor  ?  —  A.  It 
transmits  the  rays  of  Hght,  and  aids  the  free  motions  of 
the  u'is. 

Q.  'What  are  its  boundaries  ?  —  A.  It  fills  the  interval 
between  the  cornea  and  crystalline  lens. 

Q.  Describe  the  aqueous  humor. — A.  It  is  a  bright 
limpid  fluid,  and  in  properties  bears  some  resemblance 
to  the  \-itreous. 

Q.  What  is  the  composition  of  both  these  humors  ? 
—  A.  They  are  composed  of  albumen,  gelatine,  and 
mm'iate  of  soda,  held  in  solution  by  an  aqueous  men- 
struum. 

Q.  How  is  this  fluid  secreted?  —  A.  By  secretion  from 
the  transparent  walls  of  its  capsule. 

CRYSTALLINE  LENS. 

Q.  "What  is  the  use  of  the  crystalline  lens?  —  A.  It 
concentrates  the  rays  of  Hght,  so  as  to  make  a  distinct 
image  in  the  posterior  chamber. 

Q.  Where  is  the  crystalline  lens  situated  ?  —  A.  Be- 
tween the  aqueous  and  vitreous  humors. 

Q.  By  what  is  the  crystalline  lens  enclosed?  —  A. 
By  a  tunic,  called  tunica  crystalluia. 

VITREOUS  HUMOR. 

Q.  What  is  the  vitreous  hmnor,  and  where  is  it  situ- 
ated ? —  A.  It  is  the  most  bulky  humor  of  the  eye ;  of 
a  jelly-like  consistence,  yet  quite  transparent,  and  occu- 
pies that  portion  of  the  eyeball  posterior  to  the  crystal- 
line lens. 

Q.  What  is  the  use  of  the  vitreous  humor  ?  —  A.  It 
supports  the  form  of  the  eye,  and  maintains  the  other 
humors  in  theu*  proper  positions. 


EESPIEATORY    SYSTEM. 


PHYSIOLOGICAL    CONSIDERATIONS. 

Respiration  and  Structure  of  the  Lungs. — 
The  organs  of  respiration  are  the  larynx, 
the  upper  opening  of  which  is  named  glottis, 
the  trachea  or  windpipe,  bronchia,  and  the 
lungs. 

The  air  is  displaced  out  of  the  lungs  by 
the  action  of  the  muscles  of  respkation; 
and,  when  these  relax,  the  lungs  expand  to 
a  certain  calibre  by  their  elasticity.  This 
may  be  exemplified  by  means  of  a  sponge, 
which  may  be  compressed  into  a  small  bulk 
by  the  hand,  but,  upon  opening  the  same, 
the  sponge  returns  to  its  natm-al  size,  and 
all  its  cavities  become  filled  with  air.  The 
purification  of  the  blood  in  the  lungs  is  of 
vital  importance,  and  indispensably  neces- 
sary to  the  due  performance  of  all  the  func- 
tions. "When  the  lungs,  and  muscles  con- 
nected with  them,  are  in  a  physiological 
state,  the  horse  is  said  to  be  in  good  wind — 
a  very  desirable  state  for  an  animal  to  be 
in,  whose  usefiilness  depends  on  his  being 
capable  of  a  long  continuance  of  quick 
motion.  The  trachea,  or  windpipe,  after 
dividing  into  bronchia,  again  subdivides  into 
innumerable  other  branches,  the  extremities 
of  which  compose  an  infinite  quantity  of 
small  cells,  which,  with  the  ramifications  of 
the  veins,  arteries,  nerves,  lymphatics,  and 
the  connecting  cellular  membrane,  make  up 
the  whole  mass  or  substance  of  the  lungs. 
The  internal  surface  of  the  windpipe,  bron- 
chia, and  air-cell,  is  lined  with  a  membrane, 
which  secretes  a  mucous  fluid:  when,  in  con- 
sequence of  an  obstructed  surface,  this  fluid 
becomes  abundant,  it  is  expelled  by  the 
nostrils.  The  whole  is  invested  with  a 
thin,  transparent  membrane,  named  pleura : 
the  same  membrane  lines  the  internal  sur- 
face of  the  ribs  and  diaphragm,  and,  by  a 


duplicature  of  its  folds,  forms  a  separation 
between  the  lobes  of  the  lungs. 

RESPIRATORY    SYSTEM. 

The  function  of  respiration  is  the  conver- 
sion of  venous  into  arterial  blood.  This 
arterialization  of  the  venous  blood  is  a  pro- 
cess highly  essential  to  the  well-being  of 
all  animals ;  more  important  is  it  than  the 
assimulation  of  aliment;  for  a  horse  may 
live  several  days  without  food,  yet  cannot 
exist  many  minutes  unless  his  blood  be 
arterialized. 

In  considering  the  function  of  respiration, 
our  attention  is  first  turned  to  the  mechani- 
cal means  by  which  the  air  is  alternately 
admitted  and  discharged  from  the  lungs. 
The  mechanical  act  of  respiration  is  divisi- 
ble into  two  periods,  that  of  inspu-ation, 
during  which  air  is  drawn  into  the  lungs  so 
as  to  increase  its  volume  and  distend  its 
parenchema  and  expiration,  during  which 
process  the  air  wliich  had  been  so  received 
is  expelled. 

Inspiration  is  accompanied  by  enlarge- 
ment of  the  capacity  of  the  thorax  in  its 
various  dimensions.  This  is  effected  by  the 
action  of  different  sets  of  muscles,  operated 
on  by  the  nervous  system.  The  principal 
muscle  of  inspiration  is  the  diaphragm. 

Among  the  secondary  muscles  employed 
in  inspiration  are  those  which  articulate  the 
ribs,  viz.,  the  intercostales.  Each  rib  is 
capable  of  a  small  degree  of  motion  on  the 
extremity  by  which  it  is  articulated  with 
the  vertebrsB.  This  motion  is  chiefly  for- 
ward and  backward ;  the  intercostal  muscles 
favor  this  motion,  as  they  are  disposed  in 
two  layers,  each  passing  obliquely,  but  with 
opposite  inclinations,  from  one  to  the  adja- 
cent rib.     There  are  two  ways  in  which  the 

(144) 


ANATOMY  AND   PHYSIOLOGY   OF   THE  HOESE. 


145 


chest  may  be  dilated:  first,  by  the  dia- 
phragm ;  and  secondly,  by  the  intercostales, 
which  elevate  the  ribs.  In  natural  respira- 
tion, the  horse  breathes  chiefly  through  the 
aid  of  the  diaphragm.  Should  the  respira- 
tion become  quickened,  the  intercostales  are 
employed,  and,  when  the  respiration  is  labo- 
rious, the  axillary  muscles  of  the  abdomen, 
back,  and  sides,  are  brought  into  use. 

The  glottis  is  opened  dm-ing  inspkation 
by  the  muscles  of  the  larynx. 

The  expulsion  of  the  air  from  the  lungs 
constitutes  expiration.  This  takes  place 
as  soon  as  the  air  which  has  been  ex- 
pired has  parted  with  its  oxygen,  and  re- 
ceived in  return  a  certain  quantity  of  car- 
bonic acid  gas  and  vapor.  In  regard  to  the 
elasticity  of  the  lungs,  it  is  now  demon- 
strated that  they  possess  no  inherent  power 
of  elasticity  other  than  that  common  with 
all  membranous  textures.  Hence,  if  an 
opening  be  made  in  the  sides  of  the  chest, 
the  lobes  on  this  side  collapse  in  consequence 
of  the  pressure  of  air  from  without. 

We  have  next  to  inquire  what  changes 
have,  in  the  meanwhile,  been  eflected  in  the 
blood  by  the  action  of  the  air  to  which  it 
has  been  subjected  in  the  lungs.  A  visible 
alteration,  in  the  first  place,  is  produced  in 
its  ciilor,  which,  from  being  of  a  dark  pur- 
ple, nearly  approaching  to  black,  when  it 
arrives  at  the  air-cells  by  the  pulmonary 
arteries,  has  acquired  the  bright,  intensely 
scarlet  hue  of  arterial  blood,  when  brought 
back  to  the  heart  by  the  pulmonary  veins. 
Li  other  respects,  however,  its  sensible 
qualities  do  not  appear  to  have  undergone 
any  material  change.  Judging  from  the 
changes  produced  on  the  air  which  has 
been  in  contact  with  it,  we  are  warranted  in 
the  inference  that  it  has  parted  with  a 
certain  quantity  of  carbonic  acid  and  of 
water,  and  that  it  has  in  return  acquired  a 
certain  proportion  of  oxygen.  Since  it  has 
been  found  that  the  quantity  of  oxygen 
absorbed  is  greater  than  that  which  enters 
into  the  composition  of  the  carbonic  acid 
evolved,  it  is  obvious  that  at  least  the  excess 
of  oxygen  is  directly  absorbed  by  the  blood ; 

19 


ana  this  absorption  constitutes,  no  doubt, 
an  essential  part  of  its  arterialization. 

It  has  been  much  disputed  whether  the 
combination  which  seems  to  be  effected  be- 
tween the  oxygen  of  the  air  and  the  carbon 
furnished  by  the  blood,  occurs  during  the 
act  of  respiration,  and  takes  place  in  the 
air-ceUs  of  the  lungs,  or  whether  it  takes 
place  in  the  course  of  circulation.  On  the 
first  hypothesis,  the  chemical  process  would 
be  very  analogous  to  the  simple  combustion 
of  charcoal,  which  may  be  conceived  to  be 
contained  in  the  venous  blood  in  a  free 
state,  exceedingly  divided,  and  ready  to 
combine  with  the  oxygen  of  the  air,  and 
imparting  to  that  venous  blood  its  charac- 
teristic dark  color ;  while  arterial  blood,  from 
which  the  carbon  had  been  eliminated, 
would  exhibit  the  red  color  natural  to  blood. 
On  the  second  hypothesis,  we  must  suppose 
that  the  whole  of  the  oxygen,  which  disap- 
pears from  the  au'  respired,  is  absorbed  by 
the  blood  in  the  pulmonary  capillaries,  and 
passes  on  with  it  into  the  systemic  circu- 
lation. The  blood  becoming  venous  in  the 
course  of  the  circulation,  by  the  different 
processes  to  which  it  is  subjected  for  sup- 
plying the  organs  with  the  materials  re- 
quired in  the  exercise  of  their  respective 
functions,  the  proportion  of  carbon  which  it 
contains  is  increased,  both  by  the  abstrac- 
tion of  the  other  elements,  and  by  the  addi- 
tion of  nutritive  materials  prepared  by  the 
organs  of  digestion.  The  oxygen,  which 
had  been  absorbed  by  the  blood  in  the  lungs, 
now  combines  with  the  redundant  carbon, 
and  forms  with  it  either  oxide  of  carbon, 
or  carbonic  acid,  which  is  exhaled  dming  a 
subsequent  exposure  to  the  air  in  the  lungs. 
Many  facts  tend  strongly  to  confirm  our 
belief  in  the  latter  of  these  hypotheses. 

OF    THE    LARYNX.* 

The  larynx  is  the  organ  producing  the 
voice  of  the  animal. 

Situation. — It  is  joined  to  the  top  of  the 
trachea  (or  windpipe),  and  is  placed  in  the 
throat,  between  the  posterior  and  broadest 
*  Percivall's  Hippopathology. 


148 


ANATOMY   AND   PHYSIOLOGY   OP 


quarter  of  an  inch  in  thickness — evidently 
made  so  substantial  to  resist  external  in- 
jury; whereas  its  posterior  or  unexposed 
parts  grow  suddenly  thin  and  yielding,  and 
taper  to  the  extremities  ;  which,  instead  of 
meeting  and  uniting,  pass  one  over  the 
other,  and  thus  form  a  shield  of  defence 
behind,  while  they  admit  of  a  certain  dila- 
tation and  contraction  of  the  internal 
dimensions  of  the  tube.  These  attenuated 
ends  are  joined  together  by  a  ligamentous 
expansion,  mingled  wdth  a  quantity  of  cel- 
lular membrane.  The  rings  are  likewise 
attached  to  one  another  by  narrow  ligamen- 
tary  bands,  strong  and  elastic ;  which,  after 
they  have  been  drawn  apart  in  certain  posi- 
tions of  the  head  and  neck,  have  the  power 
to  approximate  them  ;  when  the  pipe  is  re- 
moved from  the  body,  and  suspended  by 
the  uppermost  ring,  these  ligaments  coun- 
teract the  tendency  its  weight  has  to  sepa- 
rate the  rings,  and  still  maintain  them  in 
apposition.  The  lowermost  ten  or  twelve 
pieces  of  cartilage  appear  on  examination 
but  ill  to  desers-e  the  name  of  rings  ;  indeed, 
they  are  little  more  than  semi-annular,  the 
deficiences  in  them  behind  being  made 
good  by  intermediate  moveable  pieces  of 
cartilage.  These  pieces,  whose  breadth  in- 
creases as  we  descend,  are  let  into  the 
vacuities  in  such  manner  as  to  overlap  the 
terminations  of  the  segments,  and  they  are 
confined  and  concealed  by  the  same  sort  of 
ligamentary  and  cellular  investment  as  was 
before  noticed. 

Muscle. — 'Where  the  outward  extremity 
of  the  ring  suddenly  turns  inward,  and  de- 
generates into  a  thin  flexible  flap  on  either 
side,  a  band  of  muscular  fibres  is  fixed  and 
stretched  across  the  canal,  dividing  it  into 
two  unequal  semi-elliptical  passages.  The 
anterior  one  is  the  proper  air  channel ;  the 
posterior  or  smaller  one  is  filled  with  a  fine 
reticular  membrane,  connecting  the  band  to 
the  posterior  part  of  the  ring,  and  preventing 
i  in  action,  from  encroaching  upon  the  main 
conduit.  This  self-acting  band  appears  to 
me  to  have  been  added  to  the  tube  to  enable 
it  to  enlarge  its  caliber — not  to  diminish  it, 
as  a  superficial  view  of  these  parts  might 


lead  one  to  imagine ;  for,  in  consequence  of 
the  passage  being  naturally  elliptical,  and 
the  muscle  being  extended  across  its  long 
diameter,  the  contraction  of  its  sides  will 
give  the  tube  a  circular  figure,  by  increasing 
the  curvature  of  the  ring  anteriorly,  and 
thereby,  in  effect,  wiU  expand  and  not  con- 
tract the  caliber  of  the  canal.  I  would  say, 
then,  that  the  trachea  was  made  muscular 
in  order  that  it  might  have  the  power  of  in- 
creasing its  capacity  for  the  passage  of  air, 
whenever  the  lungs  were  called  into  extra- 
ordinary action :  in  addition  to  which,  I 
think  that  this  band  may,  in  some  degree, 
counteract  any  tendency  certain  positions  of 
the  head  and  neck  have  to  alter  its  shape 
and  diminish  its  circumference.  This 
opinion  is  corroborated  by  the  circumstance, 
that  the  muscle  grows  slender  and  pale  as 
we  approach  the  lower  end  of  the  pipe, 
where  the  canal  itself  is  nearly  circular,  and 
where  it  is  placed  in  the  least  moveable 
part  of  the  neck.* 

Membrane,  —  The  trachea  is  lined  by  a 
soft,  pale  red  membrane,  which  anteriorly 
has  a  close  adhesion  to  the  rings  them- 
selves, and  presents  a  smooth,  polished  in- 
ternal surface  ;  but  which,  posteriorly,  is 
loosely  attached  to  the  muscular  band,  and 
puckered  into  fourteen  or  fifteen  longitu- 
dinal pliccB  or  folds,  that  extend  with  regu- 
larity from  one  end  of  the  tube  to  the 
other.  These  folds  were  evidently  made  to 
allow  of  the  contraction  and  elongation  of 
tliis  muscular  band ;  for  I  cannot  myself 
assign  any  reason  why  they  should  exist  in 
its  relaxed  state,  unless  this  fulness  of 
membrane  be  given  to  admit  of  enlarge- 
ment of  the  caliber  of  the  tube  during  the 
contractions  of  that  muscle  ;  if  this  be 
plausible,  I  may  adduce  the  coiTUgation  of 
the  membrane  as  another  proof  that  the 
caliber  of  the  trachea  is  susceptible  of  aug- 
mentation. This  membrane  is  continuous 
with  that  which  clothes  the  rima  glottidis ; 

*  In  tliis  opinion,  says  Mr.  Pcrcivall,  I  find  I  am  at 
variance  with  Girard.  The  French  professor  ascribes  to 
it  the  power  of  contracting  the  caliber  of  the  trachea.  "  Cette 
couche,  bien  evidemment  musculeuse,  pent  retrecir  le  cal- 
ibre de  la  trachee,  en  rapportant  les  extremites  des  seg- 
mens." — Anat.  Fc<.,p.l46  et  147,  torn.  ii. 


THE   HORSE. 


149 


but  it  is  paler  than  it,  and  not  near  so  sensi- 
tive. Its  arterial  ramifications,  also  less 
abundant  than  upon  the  glottis,  exhale  a 
vapor  from  its  surface ;  independently  of 
which,  it  is  kept  continually  lubricated  by 
mucus,  furnished  from  its  numerous  lacuucB, 
to  defend  it  from  anything  acriminous  that 
may  be  contained  in  the  breath. 

Bronchial  Tubes.  —  The  trachea  having 
entered  the  thorax,  bifurcates  into  the  two 
bronchial  tubes.  Of  them,  the  right  is  the 
more  capacious  canal,  on  account  of  having 
communication  with  the  larger  division  of 
the  lungs  ;  the  left  the  longer  one,  in  conse- 
quence of  having  to  cross  under  the  pos- 
terior aorta,  in  its  com'se  to  the  left  division 
of  the  lungs.  The  last  cartilage  of  the 
main  pipe  has  a  spear-like  or  angular  pro- 
jection extending  down  betAveen  the  bron- 
chial tubes,  filling  up  that  space  which 
would  otherwise  be  left  open  from  the  di- 
vergent manner  in  which  they  branch  off": 
it  is  quite  loosely  attached,  in  order  that 
the  branches  may  accommodate  themselves 
to  the  motions  of  the  neighboring  parts. 
The  bronchial  tubes  vary  in  structure  from 
the  trunk  that  gives  origin  to  them:  instead 
of  their  rings  being  formed  of  entire  pieces 
of  cartilage,  they  are  constituted  of  several 
separate  pieces,  making  up  so  many  segments 
of  the  circle,  overlapping  one  another,  and 
united  together  and  invested  by  an  elastic 
cellular  substance :  they  also  differ  in  hav- 
ing no  muscular  band,  another  fact  connected 
with  the  physiology  of  that  part.  The  bron- 
chial tubes,  in  penetrating  the  substance  of 
the  lungs,  subdivide  —  the  right  into  tln:ee 
principal  branches,  the  left  into  two  ;  from 
which  spring  innumerable  others,  that  grow 
smaller  and  smaller,  until  the  ramifications 
become  so  reduced  that  they  are  no  longer 
traceable  by  the  naked  eye.  Li  the  larger 
branches,  we  may  dissect  out  five  and  even 
six  segments  of  cartilage,  held  together  by 
a  thin  but  dense  and  elastic  cellular  sub- 
stance ;  in  the  smaller  divisions,  only  two 
are  found,  and  they  are  diminished  in  size ; 
and,  in  the  smallest  visible  ramifications  of 
all,  cartilage  is  altogether  wanting,  though, 
in  many  places,  marks  of  the  rings  may  be 


traced  upon  the  continuation  of  the  lining 
membrane,  which  in  these  intimate  parts 
compose  the  entire  parietes  of  the  tube. 
In  the  larger  branches  this  membrane 
(which  is  continuous  throughout  the  bron- 
chial system)  assumes  a  plicated  disposi- 
sition  —  apparently,  to  admit  the  more 
readily  of  expansion. 

THYROID    GLANDS. 

Two  egg-shaped,  apparently  glandular 
bodies,  attached  just  below  the  larynx  to 
the  sides  of  the  trachea,  and  united  in  front 
of  that  tube  by  an  intervening  portion  of 
the  same  substance,  which,  by  way  of  dis- 
tinction, is  by  some  called  the  isthmus. 
They  are  enveloped  and  attached  in  their 
situation  by  cellular  membrane  ;  are  larger 
and  more  vascular  in  the  young  than  in 
the  old  subject ;  and  exhibit  a  spongy  tex- 
ture, when  cut  into,  which  I  am  at  present 
ignorant  of  the  precise  nature  of.  They 
are  well  supplied  with  blood-vessels,  and 
have  many  smaU  nerves  going  to  them. 
Their  physiology  still  remains  obscure. 

OF    THE    LUNGS    AND    PLEURA. 

The  lungs  are  the  essential  organs  of  res- 
piration: the  pleura  is  but  the  membrane 
by  which  they  are  invested. 

PLEURA. 

The  pleura  is  a  fine,  semi-transparent 
membrane,  lining  the  cavity  of  the  chest, 
and  giving  a  covering  to  the  lungs.  By 
that  portion  of  it  which  is  called  the  medi- 
astinum,  the  cavity  is  divided  into  the  right 
and  left  sides  of  the  thorax. 

General  Conformation.  —  If  the  lungs  be 
exposed,  by  breaking  off"  one  or  two  of  the 
ribs,  we  shall  perceive  that  their  surface,  as 
well  as  that  of  the  cavity  itself,  is  every- 
where smooth,  poHshed,  and  humid.  This 
is  owing  to  the  extensive  investment  of  the 
pleura,  the  surface  of  which  is  now  pre- 
sented ;  so  that,  in  reality,  without  break- 
ing the  surface,  nothing  but  pleura  can  be 
touched  ;  although,  from  its  extreme  tenuity 
and  pellucidity,  the  viscera  appear,  on  a 
superficial  view,  to  present  their  own  bare 


148 


ANATOMY   AND   PHYSIOLOGY   OF 


quarter  of  an  inch  in  thickness — evidently 
made  so  substantial  to  resist  external  in- 
jury ;  whereas  its  posterior  or  unexposed 
parts  grow  suddenly  thin  and  yielding,  and 
taper  to  the  extremities  ;  which,  instead  of 
meeting  and  uniting,  pass  one  over  the 
other,  and  thus  form  a  shield  of  defence 
behind,  while  they  admit  of  a  certain  dila- 
tation and  contraction  of  the  internal 
dimensions  of  the  tube.  These  attenuated 
ends  are  joined  together  by  a  ligamentous 
expansion,  mingled  with  a  quantity  of  cel- 
lular membrane.  The  rings  are  likewise 
attached  to  one  another  by  narrow  ligamen- 
tary  bands,  sti'ong  and  elastic ;  which,  after 
they  have  been  drawn  apart  in  certain  posi- 
tions of  the  head  and  neck,  have  the  power 
to  approximate  them  ;  when  the  pipe  is  re- 
moved from  the  body,  and  suspended  by 
the  uppermost  ring,  these  ligaments  coun- 
teract the  tendency  its  weight  has  to  sepa- 
rate the  rings,  and  still  maintain  them  in 
apposition.  The  lowermost  ten  or  twelve 
pieces  of  cartilage  appear  on  examination 
but  ill  to  deserve  the  name  of  rings  ;  indeed, 
they  are  little  more  than  semi-annular,  the 
deficiences  in  them  behind  being  made 
good  by  intermediate  moveable  pieces  of 
cartilage.  These  pieces,  whose  breadth  in- 
creases as  we  descend,  are  let  into  the 
vacuities  in  such  manner  as  to  overlap  the 
terminations  of  the  segments,  and  they  are 
confined  and  concealed  by  the  same  sort  of 
ligamentary  and  cellular  investment  as  was 
before  noticed. 

Muscle. —  Where  the  outward  extremity 
of  the  ring  suddenly  turns  inward,  and  de- 
generates into  a  thin  flexible  flap  on  either 
side,  a  band  of  muscular  fibres  is  fixed  and 
stretched  across  the  canal,  dividing  it  into 
two  unequal  semi-elliptical  passages.  The 
anterior  one  is  the  proper  air  channel ;  the 
posterior  or  smaller  one  is  filled  with  a  fine 
reticular  membrane,  connecting  the  band  to 
the  posterior  part  of  the  ring,  and  preventing 
i  in  action,  from  encroaching  upon  the  main 
conduit.  This  self-acting  band  appears  to 
me  to  have  been  added  to  the  tube  to  enable 
it  to  enlarg^e  its  caliber — not  to  diminish  it, 
as  a  superficial  view  of  these  parts  might 


lead  one  to  imagine  ;  for,  in  consequence  of 
the  passage  being  naturally  elliptical,  and 
the  muscle  being  extended  across  its  long 
diameter,  the  contraction  of  its  sides  will 
give  the  tube  a  circular  figure,  by  increasing 
the  curvature  of  the  ring  anteriorly,  and 
thereby,  in  effect,  will  expand  and  not  con- 
tract the  caliber  of  the  canal.  I  would  say, 
then,  that  the  trachea  was  made  muscular 
in  order  that  it  might  have  the  power  of  in- 
creasing its  capacity  for  the  passage  of  air, 
whenever  the  lungs  were  called  into  extra- 
ordinary action :  in  addition  to  which,  I 
think  that  this  band  may,  in  some  degree, 
counteract  any  tendency  certain  positions  of 
the  head  and  neck  have  to  alter  its  shape 
and  diminish  its  circumference.  This 
opinion  is  corroborated  by  the  circumstance, 
that  the  muscle  grows  slender  and  pale  as 
we  approach  the  lower  end  of  the  pipe, 
where  the  canal  itself  is  nearly  circular,  and 
where  it  is  placed  in  the  least  moveable 
part  of  the  neck.* 

Me^nbrane.  —  The  trachea  is  lined  by  a 
soft,  pale  red  membrane,  which  anteriorly 
has  a  close  adhesion  to  the  rings  them- 
selves, and  presents  a  smooth,  polished  in- 
ternal surface  ;  but  which,  posteriorly,  is 
loosely  attached  to  the  muscular  band,  and 
puckered  into  fourteen  or  fifteen  longitu- 
dinal plicw  or  folds,  that  extend  with  regu- 
larity from  one  end  of  the  tube  to  the 
other.  These  folds  were  evidently  made  to 
allow  of  the  contraction  and  elongation  of 
this  muscular  band  ;  for  I  cannot  myself 
assign  any  reason  why  they  should  exist  in 
its  relaxed  state,  unless  this  fulness  of 
membrane  be  given  to  admit  of  enlarge- 
naent  of  the  caliber  of  the  tube  during  the 
contractions  of  that  muscle  ;  if  this  be 
plausible,  I  may  adduce  the  corrugation  of 
the  membrane  as  another  proof  that  the 
caliber  of  the  trachea  is  susceptible  of  aug- 
mentation. This  membrane  is  continuous 
with  that  which  clothes  the  rima  glottidis ; 

*  In  this  opinion,  sajs  Mr.  Pcrcivall,  I  find  I  am  at 
variance  with  Girard.  The  French  professor  ascribes  to 
it  the  power  of  cont ractim/  the  caliber  of  the  trachea.  "  Cette 
couche,  bien  evidenimcnt  musculeuse,  pent  retrecir  le  cal- 
ibre de  la  trachee,  en  rapportant  les  extremites  des  seg- 
mens." — Anat.  F£^,p.l46  et  147,  torn.  ii. 


THE   HORSE. 


149 


but  it  is  paler  than  it,  and  not  near  so  sensi- 
tive. Its  arterial  ramifications,  also  less 
abundant  than  upon  the  glottis,  exhale  a 
vapor  from  its  surface ;  independently  of 
which,  it  is  kept  continually  lubricated  by 
mucus,  furnished  from  its  numerous  lacunce, 
to  defend  it  from  anything  acriminous  that 
may  be  contained  in  the  breath. 

Bronchial  Tubes.  —  The  trachea  having 
entered  the  thorax,  bifurcates  into  the  two 
hroncliial  tubes.  Of  them,  the  right  is  the 
more  capacious  canal,  on  account  of  having 
communication  with  the  larger  division  of 
the  lungs  ;  the  left  the  longer  one,  in  conse- 
quence of  having  to  cross  under  the  pos- 
terior aorta,  in  its  course  to  the  left  division 
of  the  lungs.  The  last  cartilage  of  the 
main  pipe  has  a  spear-lilce  or  angular  pro- 
jection extending  down  between  the  bron- 
chial tubes,  filling  up  that  space  which 
would  otherwise  be  left  open  from  the  di- 
vergent manner  in  which  they  branch  off: 
it  is  quite  loosely  attached,  in  order  that 
the  branches  may  accommodate  themselves 
to  the  motions  of  the  neighboring  parts. 
The  bronchial  tubes  vary  in  structure  from 
the  trunk  that  gives  origin  to  them:  instead 
of  their  rings  being  formed  of  entire  pieces 
of  cartilage,  they  are  constituted  of  several 
separate  pieces,  making  up  so  many  segments 
of  the  circle,  overlapping  one  another,  and 
united  together  and  invested  by  an  elastic 
cellular  substance  :  they  also  differ  in  hav- 
ing no  muscular  band,  another  fact  connected 
with  the  physiology  of  that  part.  The  bron- 
chial tubes,  in  penetrating  the  substance  of 
the  lungs,  subdivide  —  the  right  into  tln-ee 
principal  branches,  the  left  into  two  ;  from 
which  spring  innumerable  others,  that  grow 
smaller  and  smaller,  until  the  ramifications 
become  so  reduced  that  they  are  no  longer 
traceable  by  the  naked  eye.  Li  the  larger 
branches,  we  may  dissect  out  five  and  even 
six  segments  of  cartilage,  held  together  by 
a  thin  but  dense  and  elastic  cellular  sub- 
stance ;  in  the  smaller  divisions,  only  two 
are  found,  and  they  are  diminished  in  size ; 
and,  in  the  smallest  visible  ramifications  of 
all,  cartilage  is  altogether  wanting,  though, 
in  many  places,  marks  of  the  rings  may  be 


traced  upon  the  continuation  of  the  lining 
membrane,  which  in  these  intimate  parts 
compose  the  entire  parietes  of  the  tube. 
In  the  larger  branches  this  membrane 
(which  is  continuous  throughout  the  bron- 
chial system)  assumes  a  plicated  disposi- 
sition — ^apparently,  to  admit  the  more 
readily  of  expansion. 

THYROID    GLANDS. 

Two  egg-shaped,  apparently  glandular 
bodies,  attached  just  below  the  larynx  to 
the  sides  of  the  trachea,  and  united  in  fi-ont 
of  that  tube  by  an  intervening  portion  of 
the  same  substance,  which,  by  way  of  dis- 
tinction, is  by  some  called  the  isthmus. 
They  are  enveloped  and  attached  in  their 
situation  by  cellular  membrane  ;  are  larger 
and  more  vascular  in  the  young  than  in 
the  old  subject;  and  exhibit  a  spongy  tex- 
ture, when  cut  into,  which  I  am  at  present 
ignorant  of  the  precise  nature  of.  They 
are  well  supplied  with  blood-vessels,  and 
have  many  small  nerves  going  to  them. 
Their  physiology  still  remains  obscm^e. 

OF    THE    LUNGS    AND    PLEURA. 

The  lungs  are  the  essential  organs  of  res- 
piration :  the  pleura  is  but  the  membrane 
by  which  they  are  invested. 

PLEURA. 

The  pleura  is  a  fine,  semi-transparent 
membrane,  lining  the  cavity  of  the  chest, 
and  giving  a  covering  to  the  lungs.  By 
that  portion  of  it  which  is  called  the  medi- 
astimun,  the  cavity  is  divided  into  the  right 
and  left  sides  of  the  thorax. 

General  Conformation.  —  If  the  lungs  be 
exposed,  by  breaking  off  one  or  two  of  the 
ribs,  we  shall  perceive  that  their  surface,  as 
well  as  that  of  the  cavity  itself,  is  every- 
where smooth,  polished,  and  humid.  This 
is  owing  to  the  extensive  investment  of  the 
pleura,  the  surface  of  which  is  now  pre- 
sented ;  so  that,  in  reality,  without  break- 
ing the  surface,  nothing  but  pleura  can  be 
touched  ;  although,  from  its  extreme  tenuity 
and  pellucidity,  the  viscera  appear,  on  a 
superficial  view,  to  present  their  own  bare 


150 


ANATOMY    AND   PHYSIOLOGY   OF 


exterior.  Its  other  side,  on  the  contrary,  is 
rongh,  having  numerous  ceHular  llocculcnt 
appendages,  by  wliich  it  is  united  to  the 
parts  it  invests ;  and  so  close  and  firm  are 
these  adhesions,  that  to  cleanly  detach  it, 
in  the  recent  subject,  is  a  very  diiiicult  and 
tedious  dissection. 

The  pleura  is  a  reflected  membrane  ;  by 
which  is  meant,  one  that  not  only  lines  the 
cavity  in  which  the  viscera  lie  enclosed,  but 
by  duplicature,  or  vv^hat  in  anatomical  lan- 
guage is  called  reflection,  gives  a  partial  or 
complete  covering  to  the  contained  organs 
themselves.  It  is  evident,  therefore,  that 
such  a  membrane  admits  of  division  into 
two  portions  —  a  lining-  or  parietal,  and  a 
reflected  portion  ;  and  these,  with  regard  to 
the  pleura,  have,  for  the  sake  of  more  de- 
finite description,  received  the  names  of 
pleura  costalis  and  pleura  pulmonalis.  They 
are  both,  however,  continuous  at  all  points, 
are  precisely  similar  in  structure  and  func- 
tion, and,  in  fact,  are  still  but  one  and  the 
same  plem'a. 

Mediastinum.  —  There  is  yet  a  third  por- 
tion of  this  membrane  to  which  a  distinct 
appellation  has  been  given,  and  that  is  the 
mediastinum,  the  membranous  partition  be- 
tween the  cavities  or  sides  of  the  thorax ; 
it  differs  from  both  the  others  in  being  com- 
posed of  two  layers,  which  are  derived  from 
the  two  pleurae  of  the  opposite  sides. 
If  we  conceive  the  pleurae  of  the  two  sides 
of  the  thorax  to  be  perfect  sacs  or  bags, 
with  flattened  sides  turned  inwardly,  and 
closely  applied  and  united  together,  in  such 
a  manner  that  the  double  membrane  formed 
by  their  union  extends  through  the  middle 
of  the  chest,  from  the  dorsal  vertebrte  to 
the  sternum,  we  shall  at  once  have  a  toler- 
ably correct  idea  of  the  formation  as  well 
as  situation  of  the  mediastinum. 

Structure.  —  The  pleura,  from  the  nature 
of  its  secretion,  is  one  of  those  included 
in  the  list  of  serous  membranes  to  which  it 
has  been  demonstrated  also  to  be  similar  in 
its  intimate  organization.  Like  them,  it 
presents  a  shining  secreting  surface,  of  a 
whitish  aspect,  and  considerable  transpa- 
rency, and  is  composed  of  little  else  than 


condensed  cellular  substance,  whose  texture 
is  penetrated  by  blood-vessels,  absorbents, 
and  nerves :  by  long  maceration  in  water, 
indeed,  it  may  be  entirely  resolved  into  cel- 
lular substance.  In  most  parts  it  is  ex- 
tremely thin,  and  by  no  means  tough ;  but 
it  is  not  so  in  all,  for  that  portion  which 
faces  the  diaphragm  is  much  denser  and 
stronger  than  the  pulmonary  or  costal  di- 
vision of  it. 

Organization.  —  The  arteries  of  the 
pleura,  which  come  from  the  adjacent  parts, 
are  in  the  natural  state  exceeding  small,  ad- 
mitting only  the  colorless  parts  of  the  blood 
—  a  circumstance  that  accounts  for  its  pel- 
lucidity  ;  under  inflammation,  however, 
they  contain  red  blood,  and  such  is  the  ex- 
planation of  that  arborescent  vascularity 
upon  the  sides  of  the  thorax  in  horses  that 
die  of  pnuemonia ;  than  which  state  noth- 
ing can  better  demonstrate  the  comparative 
number  and  distribution  of  these  blood-ves- 
sels. The  majority  of  them  terminate  in 
exhalent  orifices,  from  which  is  continually 
poured,  upon  the  contiguous  surfaces  of  the 
smooth  interior  of  the  membrane,  a  serous 
fluid,  in  the  form  of  steam  or  vapor,  which 
may  at  any  time  be  rendered  visible  by 
opening  the  chest  of  an  animal  recently 
dead.  The  absorbents  of  this  membrane 
are  very  numerous ;  and,  though  their  ex- 
treme exflity  prevents  us  from  demonstrat- 
ing them  in  a  state  of  health,  yet  may  they 
often  be  seen  in  considerable  numbers  in 
horses  that  die  of  dropsy  of  the  chest ;  we 
have  also  abundant  proofs  of  their  exist- 
ence from  various  phenomena  that  occur 
in  the  diseases  of  the  part.  We  know,  for 
instance,  that  these  vessels  take  up  the 
serous  fluid  effused  in  hydrothorax,  for  they 
have  been  found  full  of  it  after  death  ;  and  it 
is  a  fact  that  no  longer  admits  of  doubt,  that 
blood,  extravasated  into  the  chest,  is  absorbed 
by  the  mouths  of  these  minute  vessels. 

The  nerves  of  the  pleura  are  too  small 
to  be  traced  by  dissection ;  but,  though  it 
is  not  possessed  of  much  sensibility  in  a 
healthy  state,  we  know,  at  least  we  presume 
from  analogy,  that  it  is  highly  sensitive  in 
the   diseased;  for   few   diseases   are    more 


EXPLANATION   OF   FIGURE  XY. 


NO.    1.  — FORE  EXTREMITIES. 

LATERAL  VIEW  OF  THE  OFF-FORE  LIMB. 

k.    Humero  cubital.  —  Flexor  bracliii. 

n.    Triceps  externus. 

o.    Pectoralis  transversalis. 

P".  Flexor  metacarpi  externus. 

s".  Extensor  metacarpi  magnus. 

f.    Extensor  metacarpi  obliquus. 

u\  Levator  humeri. 

X.  X.  Extensor  pedis. 

y.  y.  Extensor  suffraginis. 

Sr.  The  hoof. 

NO.   2. 

(VIEVr  AS  ABOVE.) 

1c'\  Humero  cubital,  or  flexor  brachii. 

m".  n".  Two  of  the  triceps  extensor  brachii. 

p".  Flexor  metacarpi  externus. 

s.     Extensor    "         magnus. 

t-  "  "  obliquus. 

u.  Levator  humeri. 

»'.  tu  Flexor  tendons. 

as".  Extensor  pedis. 

y".  y.  Extensor  sufiraginis. 

8.    Perforatus  et  perforans. 

4.  Subcutaneous  thoracic  vein. 

NO.   3. 

(THS  SAME  VIEW.) 

V\  m".  n".  Triceps  extensor  brachii. 
p".  Flexor  metacarpi  externus. 
q.     Extensor  suffraginis. 

5.  Extensor  metacarpi  magnus. 
u.     Flexor  tendons. 

x".   Extensor  pedis. 

z.     Suspensory  ligaments. 

4.     Subcutaneous  thoracic  vein. 

NO.   4. 
OSSEOUS  STRUCTURE. 

34.  Os  humeri. 

f.  Os  ulnaris. 

35.  Os  Radialis. 

g.  Trapezium. 

36.  Ossa  carpi. 


EXPLANATION    OF   FIGURE   XV.    CONTINUJiD. 

37.  Metacarpus  magnum. 
X.  "  par\-um. 

38.  Ossa  sessamoidea. 

39.  Os  suffi-aginis. 
40..  Os  corona. 
41.  Os  pedis. 

NO.    5. 

INSIDE   \1EW   OF  THE  OFF-FOUE  LEG. 

o".  Pectorales. 

r".  Flexor  metacarpi  internus. 

g".  Flexor  metacarpi  medius. 

s".  Extensor  metacarpi  raagnus. 

t".  Extensor  metacarpi  obliquus. 

tt".  v".  Flexor  tendons. 

x.^  Extensor  pedis. 

v".  Suspensory  ligament. 

6.  Radial  vein. 

8.  Bifurcation  of  the  suspensory  ligament. 

z.  Splent  bone. 

&•.  Inferior  border  of  the  hoof. 


"tPE   HORSE. 


151 


acutely  painful  in  the  human  subject  than 
pleurisy,  and  we  have  every  reason  to  be- 
heve  that  horses  suffer  much  from  the  same 
malady. 

Secretion.  —  It  has  been  observed  that 
the  exhalents  of  the  pleura  secrete  a  serous 
fluid,  which  is  emitted,  in  the  form  of  an 
exhalation  or  vapor,  into  the  cavity  of  the 
thorax ;  and  that  it  may  be  rendered  visible 
at  any  time,  if  an  animal,  recently  dead, 
be  opened  while  yet  warm  ;  or  if  an  open- 
ing be  made  into  the  chest  of  a  live  animal. 
In  either  case,  a  whitish  steam  will  be  per- 
ceived to  issue  from  the  interior  of  the 
cavity.  This  vapor,  shortly  after  death,  be- 
comes condensed  and  converted  into  a 
liquid ;  which  accounts  for  the  contiguous 
surfaces  of  the  pleura  being  moist,  and  for 
a  collection  of  more  or  less  fluid,  resem- 
bling water,  existing  in  the  most  depending 
parts  of  the  cavity.  In  consequence  of 
every  part  of  the  membrane  being  bedewed 
in  this  manner,  the  lung  itself  may  be  said 
to  be  in  an  insulated  state ;  for  the  pleura 
costalis  does  not,  philosophically  speaking, 
touch  the  pleura  pulmonalis,  nor  is  the  lat- 
ter in  actual  contact  with  the  mediastinum : 
all  friction,  therefore,  in  the  motions  of  these 
parts,  is  by  this  interfluent  secretion  effec- 
tually prevented.  In  this,  then,  consists 
the  chief  use  of  the  pleura,  viz.,  to  furnish 
a  secretion  for  the  purposes  of  lubrication 
and  facility  of  motion,  which  it  further 
promotes  by  its  extreme  glibness  of  surface. 
It  is  said  also  to  answer  the  purpose  of 
ligaments  to  the  contained  organs,  thereby 
confining  and  strengthening  them.  The  use 
of  the  mediastinum  is  to  divide  the  chest 
into  two  compartments. 

LUNGS. 

The  lungs  (by  butchers  called  the  lights) 
are  two.  spongy  bodies  formed  for  the  pur- 
pose of  respiration. 

Situation  and  Relation.  —  They  are  con- 
tained in  the  lateral  regions  or  sides  of  the 
thoracic  cavity ;  separated  from  each  other 
by  the  mediastinum  and  heart,  which  occupy 
the  middle  region.  Prior  to  any  opening 
being  made  into  the  thorax,  the  lungs  con- 


tinue to  fill  up  every  vacuity :  no  sooner, 
however,  is  a  perforation  made  into  the 
thoracic  cavity  than  they  shrink  in  volume, 
and  become  in  appearance  too  small  for  the 
spaces  they  occupy.  This  arises  from  their 
being  during  life  —  or  rather  during  the 
unopened  state  of  the  thorax  —  in  a  con- 
stant state  of  inflation  with  atmospheric 
air,  which  preserves  them  expanded ;  and 
they  suffer  collapse  of  substance  the  instant 
air  is  admitted,  in  consequence  of  the  pres- 
sure of  the  atmosphere  upon  them,  from 
which  they  were  protected  before  by  the 
parietes  of  the  thorax. 

Division.  —  The  lungs  are  two  in  num- 
ber, the  right  and  the  left  liing ;  parti- 
tioned from  each  other  by  the  mediasti- 
num. A  further  division  of  these  organs 
has  been  made  into  lobes.  That  on  the 
right  side,  the  larger  of  the  two,  consists  of 
three  lobes ;  the  left,  only  of  two.  These 
lobes,  which  are  nothing  more  than  partial 
divisions  of  the  lung  by  fissures  of  variable 
extent  through  its  substance,  serve  to  adapt 
them  more  accurately  to  the  thoracic  cavi- 
ties, and,  at  the  same  time,  render  them 
fitter  for  the  purposes  of  expansion  and 
contraction. 

Volume.  —  The  lungs  of  the  horse,  when 
inflated,  are  of  great  bulk ;  *  and  the  right 
is  the  larger  of  the  two  :  in  consequence  of 
the  heart  being  inclined  to  the  left  side,  less 
space  is  given  for  the  left  lung. 

Attachment.  —  The  lungs  are  attached, 
superiorly,  to  the  spine  (which  attachment 
is  sometimes  called  their  roots)  by  blood- 
vessels, the  divisions  of  the  trachea,  and  the 
mediastinal  portions  of  the  pleura :  every- 
where else,  in  a  healthy  subject,  they  are 
free  and  unconnected. 

Figure.  —  In  form,  the  lungs  of  the  horse 
are  very  like  those  of  the  human  subject ; 
and  the  latter  have  been  compared  to  the 
foot  of  an  ox,  to  which  the  injected  lung  of 
the  foetus  bears  indeed  much  resemblance ; 
for,  though  the  two  lungs  are  not  symmetri- 
cal, yet,  both  together,  they  put  on  this 
shape,  which  is  the  counterpart  of  that  of 

*  I  consider,  in  comparison  with  the  body,  that  they 
exceed  in  magnitude  those  of  the  human  subject. 


152 


ANATOMY   AND   PHYSIOLOGY  OF 


the  cavity  they  occupy.  With  regard  to 
their  general  figure,  however,  the  lungs  may 
be  said  to  be  conical :  being  broad  and  con- 
cave posteriorly,  where  they  arc  opposed  to 
the  convex  surface  of  the  diaphragm ;  nar- 
row and  somewhat  pointed  anteriorly,  where 
they  are  received  into  the  blind  pouches  of 
the  pleura,  in  the  space  betvveen  the  two 
first  ribs. 

Color.  —  In  color,  these  organs  vary  some- 
what, depending  upon  the  age  of  the  ani- 
mal, and  upon  the  quantity  and  distribution 
of  the  blood  they  contain.  In  thfe  young 
subject,  they  are  of  a  lighter  and  more  uni- 
form shade  than  in  the  adult.  In  perfect 
health  they  assume  a  pink  hue ;  which,  as 
age  advances,  becomes  mottled  with  purple 
and  grayish  patches.  Sometimes,  in  the 
dead  subject,  they  are  found  of  the  color  of 
the  darkest  venous  blood,  which  arises  from 
an  inordinate  congestion  of  that  fluid  within 
the  pulmonary  veins. 

Structure.  —  The  lungs  are  composed  of 
the  branches  of  arteries  and  veins,  and  of 
the  ramifications  of  the  trachea ;  all  which 
vessels  are  connected  together  by  an  abun- 
dant intervening  cellular  substance,  known 
by  the  name  of  parenchyma.  Beneath  the 
curv'e  made  within  the  chest  by  the  poste- 
rior aorta,  the  trachea  divides  into  the  two 
bronchial  tubes,  of  which  the  right  is  the 
larger,  but  the  shorter ;  the  left  the  longer, 
in  consequence  of  having  to  pass  under  the 
aorta  in  order  to  reach  the  left  lung.  Having 
entered  the  substance  of  the  lung,  the  right 
tube  divides  into  four  others ;  the  left  only 
into  three ;  which  difference  arises  from  the 
right  lung  possessing  an  additional  lobe. 
These  branches  may  be  traced  for  a  consid- 
erable extent  within  the  parenchyma,  giv- 
ing off  in  their  passage  numerous  other 
smaller  tubes  of  similar  structure ;  but,  as 
we  prosecute  our  dissection  of  them,  we 
shaU  find  that,  in  growing  smaller,  they  par- 
take less  and  less  of  the  nature  of  cartilage, 
and  that  the  extreme  ramifications  are  not 
only  entirely  membranous  in  their  composi- 
tion, but  of  so  fine  a  texture  as  to  be  per- 
fectly transparent.  It  will  be  remembered 
here,  that,  in  speaking  of  the  trachea,  a 


membranous  lining  to  it  was  described  of 
the  mucous  kind,  which,  it  was  observed, 
thence  passed  into  the  bronchial  vessels : 
now,  it  is  of  the  continuation  of  this  mem- 
brane in  an  attenuated  state  that  the  minute 
air-tuoes  appear  entirely  to  consist ;  at  the 
extremity  of  every  one  of  which  the  mem- 
brane is  prolonged  into  a  kind  of  blind  bag, 
or  cul-de-sac,  to  which  the  name  of  air-cell 
has  been  given. 

From  the  arborescent  ramification  and 
peculiar  mode  of  termination  of  the  bron- 
chical  tubes,  some  anatomists  have  com- 
pared them,  and  the  cells  at  their  extremities, 
to  a  bunch  of  grapes  —  supposing  the  stalks 
to  represent  the  ramifications  of  the  former, 
and  the  grapes  connected  with  them  the 
air-cells;  others  have  described  them  as 
having  resemblance  to  a  honeycomb :  and 
so  far  as  the  knife,  with  the  aid  of  glasses, 
can  develope  their  intimate  structure,  the 
first  is  an  apt  comparison,  insomuch  as  it 
relates  to  the  disposition  of  their  cells ; 
the  last,  insomuch  as  it  conveys  an 
idea  of  their  ready  inter-communication. 
For,  though  they  do  not  communicate 
but  through  the  ramifications  of  the  bron- 
chial tubes,  this  is  a  medium  of  inter- 
course at  once  so  general  and  free,  that 
numbers  of  them  are  inflated  at  the  same 
time  by  impelling  air  into  any  one  of  the 
larger  branches.  With  the  parenchymatous 
substance,  however,  they  have  no  commu- 
nication whatever.* 

The  blood-vessels  that  enter  into  the  com- 
position of  the  lungs  are  denominated  the 
pulmonary.  The  pulmonary  artery,  having 
taken  its  origin  from  the  right  ventricle  of  the 
heart,  winds  upward  to  the  root  of  the  left 
lung,  and  there  divides  into  the  right  and 
left    pulmonary   arteries,    which   divisions 

*  If  the  substance  of  the  hmgs  be  lacerated  or  rent 
asunder,  the  surface  ■will  be  found  to  present  a  tabulated 
aspect.  Introduce  a  blow-pipe  into  one  of  these  lobuli, 
and  all  the  other  lobules  —  the  entire  lung  —  may  be  in- 
flated from  this  one  ;  showing  the  free  communication  ex- 
isting between  them.  The  same  may  be  effected  by  in- 
jecting quicksilver.  You  may  do  the  same  with  the  inter- 
stitial substance ;  but  in  this  case  you  do  not  fill  the  lobules. 
In  fine,  the  lungs  with  their  cells  resemble  a  sponge ;  only 
that  the  connecting  tissue  has  no  communication  with  the 
sponge. 


THE   HORSE. 


163 


enter  their  correspondent  lungs.  The  rami- 
fications of  these  vessels  (which  differ  from 
other  arteries  in  having  no  anastomotic 
communications  one  with  another)  accom- 
pany those  of  the  bronchial  tubes,  and, 
like  them,  divide  and  subdivide,  grow 
smaller  and  augment  in  number,  as  they 
approach  the  air-cells  ;  upon  the  internal  * 
surfaces  of  wliich  they  become  capillary, 
and  assuma  a  texture  of  correspondent 
thinness  and  pellucidity  with  the  cells  them- 
selves. Through  these  minute  vessels  every 
particle  of  blood  is  impelled  every  time  it 
is  circulated  over  the  system,  as  was  stated 
when  on  the  blood :  a  remarkable  change 
of  color  is  thereby  effected  in  it,  and  we 
have  now  an  opportunity  of  seeing  in  what 
manner  this  fluid  is  exposed  to  the  influence 
of  atmospheric  air  for  the  purpose.  It  is 
evident  that  no  immediate  contact  can  hap- 
pen between  the  air  and  the  blood,  for  the 
thin,  transparent  side  of  the  vessel,  if  not 
that  of  the  air-cell  likewise,  must  ever  be 
interposed ;  so  that,  whatever  this  influence 
be,  it  must  take  effect  through  one  or  other 
or  both  of  these  membranes.  We  might 
conceive,  indeed,  that  such  minute  vessels 
could  not  transmit  through  them  such  a 
body  of  fluid  as  the  blood  ;  but,  when  we 
look  at  the  volume  of  the  lungs,  and  con- 
sider the  incalculable  number  of  air-cells 
they  must  contain,  the  globular  surface  of 
every  one  of  which  is  furnished  with  an  ex- 
pansion of  pulmonary  vessels,  we  shall  feel 
more  surprise  and  admiration  at  the  extreme 
division  and  diffusion  of  this  fluid  in  order 
to  receive  the  necessary  change,  than  that 
such  a  prodigious  number  of  capillaries 
should  be  equal,  in  their  united  caliber,  to 
the  pulmonary  artery  itself. 

From  the  extremities  of  the  arteries,  upon 
the  surface  of  the  air-cells,  arise  the  pul- 
monary veins.  These,  by  repeated  union 
with  one  another,  form  themselves,  first,  into 
visible  branches,  which  subsequently  become 
branches  of  larger  size,  until  at  length  they 
end  in  eight  pulmonary  venous  trunks, 
which  proceed  to,  and  by  four  openings  ter- 

*  Some  say,  "upon  the  external  surfaces." 
20 


minate  in,  the  left  auricle  of  the  heart.  The 
ramifications  of  these  veins,  unlike  the 
generality  of  others,  are  not  more  numerous 
than  those  of  their  correspondent  arteries : 
and  the  reason  for  this  is  obvious ;  for,  here, 
one  set  of  vessels  are  not  more  subject  to 
compression  than  the  other,  nor  does  the 
heart  (which  is  so  proximate  to  them)  re- 
quire any  such  aid  as  an  additional  number 
of  veins  affords  to  carry  on  the  circulation. 
The  pulmonary  veins  have  only  to  convey 
the  blood  back  to  the  heart,  after  it  has 
received  its  due  change  within  the  capil- 
laries upon  the  air-cells. 

Orga7iization.  —  Besides  the  pulmonary 
blood-vessels,  there  are  two  others,  named 
bronchial  arteries.  They  come  off,  by  one 
trunk,  from  the  posterior  aorta,  and  each 
of  them  enters  a  division  of  the  lungs,  in 
the  substance  of  which  it  branches  forth, 
and  takes  the  course  of  the  bronchial  tubes. 
These  tubes  they  supply,  as  well  as  the  coats 
of  the  pulmonary  vessels,  and  the  paren- 
chyma of  the  lungs,  with  blood :  in  fact, 
they  may  be  regarded  as  the  nutrient  ves- 
sels of  these  organs.  It  has  been,  however, 
and  still  remains,  a  subject  of  dispute, 
whether  these  vessels  do  exclusively  nourish 
the  substance  of  the  lungs  or  not ;  some 
say  that  they  do ;  while  others  assert  that 
they  are  assisted  in  this  function  by  the  pul- 
monary artery,  with  some  of  the  branches 
of  which  they  anastomose.  The  latter 
opinion  certainly  does  not  appear  to  be  sup- 
ported by  facts  of  much  weight;  on  the 
conti-ary,  the  blood  which  the  pulmonary 
arteries  contain  is  dark-colored,  and  unfit 
for  the  nutriment  of  any  organ ;  and  as  for 
anastomosis,  we  have  no  demonstrative 
proof  of  its  existence.  The  bronchial  veins 
end  in  one  trunk,  which  returns  the  blood 
into  the  vena  azygos. 

The  nerves  of  the  lungs  are  derived  prin- 
cipally from  a  large  plexus  within  the  chest, 
constituted  of  the  par  vagum  and  sympa- 
thetic. They  enter  the  pulmonary  structure 
in  company  with  the  bronchial  tubes  and 
blood-vessels,  and  continue  their  course 
with  them,  to  be  dispersed  upon  the  bron- 
chial membrane  and  parietes  of  the  air-cells. 


154 


ANATOMY  AND  PHYSIOLOGY  OF  THE  HORSE. 


The  absorbents  of  the  lungs  are  large  and 
numerous,  particularly  the  deep-seated :  and 
of  the  superficial,  we  may  often  succeed  in 
injecting  considerable  numbers,  by  intro- 
ducing a  quicksilver-pipe  under  the  pleura 
pulmonalis.  They  all  pass  through  the 
absorbent  glands  situated  around  the  roots 
of  the  bronchial  tubes. 

Parenchyma. —  The  connecting  medium 
of  the  various  constituent  parts  of  these 
organs,  or,  as  it  is  termed,  their  parenchyma^ 
appears  to  consist  of  little  else  than  cellular 
tissue,  without  any  intermixture  of  adipose 
matter :  it  admits  of  the  free  diffusion  of 
any  fluid  that  may  be  extravasated  into  it 
—  of  air  that  may  have  escaped  from  the 
air-cells,  or  of  serous  fluid  poured  out  when 
the  lungs  become  anasarcous ;  but,  as  was 
observed  before,  there  is  no  intercommuni- 
cation between  it  and  the  cells  or  vessels,  as 
long  as  the  organs  preserve  their  integrity 
of  structure. 

Specific  Gravity.  —  The  lungs,  when 
healthy,  are  exceeding  light  in  comparison 
to  their  volume ;  so  that,  if  they  be  immersed 
in  water,  unlike  most  other  parts,  they  will 
float  upon  the  surface,  —  a  fact  familiar  to 
every  one  who  has  seen  the  liver  and  lights 
of  an  animal  thrown  into  a  pail  of  water 
to  be  washed :  indeed,  the  name  of  lights 
itself  seem  to  have  been  given  to  them  from 
this  very  property.  If  the  foetal  lungs,  how- 
ever, be  so  ti'eated,  they  will  instantly  sink 
to  the  bottom  of  the  vessel :  and  this  ex- 
I^rimental  result  at  once  shows  why  those 
ol  an  animal  that  has  once  breathed  should 
swim ;  for,  in  the  one  instance  they  contain 


air,  in  the  other  they  are  wholly  free  from 
it.  They  are  not  to  be  regarded  as  respi- 
ratory organs  in  the  foetus.  It  is  evident, 
therefore,  that  the  lungs  owe  their  property 
of  lightness  to  the  air  they  contain  ;  and,  as 
a  further  proof  of  it,  if  that  air  be  by  any 
means  absorbed  or  pressed  from  them,  and 
their  bulk  diminished  by  collapse  of  the 
air-cells,  like  other  viscera,  they  will  prove 
heavier  than  an  equal  volume  of  water: 
hence  it  is  that  the  lungs  of  a  horse  that 
has  died  of  hydrothorax,  even  though  they 
be  sound,  are  of  a  greater  specific  gravity 
than  those  of  one  in  health.  It  occasionally 
happens,  however,  that  these  viscera  evince, 
in  this  particular,  the  properties  of  airless 
lung,  while  their  natural  volume  and  general 
appearance  remain  the  same :  there  must  be 
present  interstitial  deposition. 

BRONCHIAL    GLANDS. 

Small,  oval-shaped,  glandular-looking 
bodies,  situated  about  the  roots  of  the  lungs, 
adhering  more  particularly  to  the  bottom 
of  the  trachea  and  the  bronchial  tubes. 
They  exhibit  a  dirty  French  gray  hue,  inter- 
spersed with  dark  blueish  spots,  and  are 
about  the  volume  (though  this  varies  much) 
of  a  tick-bean.  For  a  long  time  the  nature 
of  these  bodies  remained  obscure :  of  late, 
skilful  injections  have  clearly  shown  them 
to  be  absorbent  glands.  They  possess  their 
capsules,  and,  when  cut  open,  exhibit  a  cel- 
lular structure.  They  contain  a  dark  fluid, 
which  will  soil  anything  it  touches  ;  whose 
principal  ingredient  chemists  have  found  to 
be  carbon. 


CIRCULATORY    SYSTEM. 


PRELIMINARY  REMARKS   (ON   THE  BLOOD, 
ETC.). 

The  appearance  of  blood  is  familiar  to 
most  persons.  It  contains  the  elements  for 
building  up  and  nourishing  the  whole  ani- 
mal structure.  On  examining  blood  with  a 
microscope,  it  is  found  full  of  little  red  glo- 
bules, which  vary  in  their  size  and  shape  in 
different  animals,  and  are  more  numerous 
in  warm  than  in  cold-blooded  animals ; 
probably  this  arises  from  the  fact  that  the 
latter  absorb  less  oxygen.  If  the  blood  of 
one  animal  be  transfused  into  another,  it 
will  frequently  cause  death. 

When  blood  stands  for  a  time  after  being 
drawn,  it  separates  into  two  parts.  One  is 
called  serum,  and  resembles  the  white  of  an 
egg ;  the  other  is  the  clot  or  crassamentum, 
and  forms  the  red  coagulum,  or  jelly-like 
substance  :  this  is  accompanied  by  whitish, 
tough  threads,  called  fibrine.  When  blood 
has  been  drawn  from  a  horse,  and  it  as- 
sumes a  cupped  or  hollow  form,  if  serum, 
or  buify  coat,  remain  on  its  surface,  it  de- 
notes an  impoverished  state ;  but  if  the 
whole,  when  coagulated,  be  of  one  uniform 
mass,  it  indicates  a  healthy  state  of  this 
fluid.  The  blood  of  a  young  horse  gen- 
erally coagulates  into  a  firm  mass,  while 
that  of  an  old  or  debilitated  one  is  gen- 
erally less  dense,  and  more  easily  divided  or 
broken  down.  The  power  that  propels  the 
blood  into  the  different  ramifications  of  the 
animal,  is  a  mechanico-vital  power,  and  is 
accomplished  through  the  medium  of  the 
heart  and  lungs  ;  the  latter  is  a  powerful 
muscular  organ  contained  in  the  chest. 
From  certain  parts  of  it  arteries  arise  ;  in 
others  the  veins  terminate ;  and  it  is  princi- 
pally by  its  alternate  contractions  and  ex- 
pansions, aided  as  already  stated,  that  the 
circulation  of  the  blood  is  carried  on.    The 


heart  is  invested  with  a  membranous  sac, 
called  pericardium,  which  adheres  to  the 
tendinous  centre  of  the  diaphragm,  and  to 
the  great  vessels  at  the  base  of  the  heart. 
The  heart  is  lubricated  by  a  serous  fluid 
within  the  pericardium,  which  guards 
against  friction.  In  dropsical  affections, 
the  quantity  of  this  fluid  is  considerably  in- 
creased, and  constitutes  a  disease  called  hy- 
drothorax.  The  heart  is  divided  into  four 
cavities,  viz.,  two  auricles,  named  from 
their  resemblance  to  an  ear,  and  two  ventri- 
cles, forming  the  body.  The  left  ventricle 
is  smaller  than  the  right ;  but  its  sides  are 
much  thicker  and  stronger :  it  is  from  this 
part  that  the  grand  trunk  of  the  arteries 
proceeds,  called  the  great  aorta.  The  right 
cavity,  or  ventricle,  is  the  receptacle  for  the 
blood  that  is  brought  back  by  the  veins 
after  going  the  rounds  of  the  circulation ; 
which,  like  an  inverted  tree,  become  larger 
and  less  numerous  as  they  approach  the 
heart,  where  they  terminate  in  the  right 
auricle.  The  auricle  on  the  left  side  of 
the  heart  receives  the  blood  that  has  been 
distributed  through  the  lungs  for  purifica- 
cation.  Where  the  veins  terminate  in  auri- 
cles, there  are  valves  placed.  The  coronary 
vein,  which  enters  the  right  auricle,  has  its 
mouth  protected  by  a  valve  called  semi- 
lunar, or  half-moon  shape,  which  opens  only 
toward  the  heart,  and  prevents  the  blood 
taking  a  retrograde  course.  The  different 
tubes  coming  from  and  entering  into  the 
heart  are  also  provided  with  valves  to  pre- 
vent the  blood  from  returning.  For  exam- 
ple, the  blood  proceeds  out  of  the  heart, 
along  the  aorta;  the  valve  opens  forward  or 
upward,  the  blood  also  moves  upward,  and 
pushes  the  valve  asunder,  and  passes 
through ;  the  pressure  from  above  effec- 
tually closes  the  passage.     The  valves  of 

(155) 


156 


ANATOMY  AND   PHYSIOLOGY   OF 


the  heart  are  composed  of  elastic  cartilage, 
which  enables  them  to  work  with  ease.  In 
some  diseases,  however,  they  become  ossi- 
fied. This,  of  course,  is  fatal.  The  heart 
and  its  appendages  are  also  subject  to  other 
diseases,  called  dilatation,  softening,  hard- 
ening, etc.  Now,  the  blood,  having  been 
brought  from  all  parts  of  the  system  by  the 
veins,  enters  into  the  vena  cava  ascending 
and  descending  portion,  which  empty  them- 
selves into  the  right  auricle ;  and  this, 
when  distended  with  blood,  contracts,  and 
forces  its  contents  into  the  right  ventricle, 
which,  contracting  in  its  turn,  propels  the 
blood  into  the  pulmonary  arteries,  whose 


numerous  ramifications  bring  it  in  con- 
tact with  the  air-cells  of  the  lungs.  It 
then  assumes  a  crimson  color,  and  is  then 
adapted  to  build  up  and  supply  the  waste. 
Having  passed  through  the  vessels  of  the 
lungs,  it  continues  on,  and  passes  into 
the  left  auricle:  this  also  contracts,  and 
forces  the  blood  through  a  valve  into  the 
left  ventricle.  This  ventricle  then  con- 
tracts in  its  turn,  and  the  blood  passes 
through  another  valve  into  the  great  aorta, 
from  which  it  is  distributed  into  the  whole 
arterial  structure :  after  going  the  rounds  of 
the  circulation,  it  is  again  returned  to  the 
heart  by  the  veins. 


EXAMINATIOXS  OX  THE  NATURE  AND  PROPERTIES  OF  BLOOD. 


Q.  What  are  the  properties  of  blood  ?  —  A.  In 
health,  it  is  a  smooth  homogenous  jBuid,  of  unctuous 
adhesive  consistence,  of  a  slightlj'  saline  taste,  and  of  a 
specific  gravity  somewhat  exceeding  that  of  water.  It 
exhales  a  vapor  which  has  a  peculiar  odor ;  this,  how- 
ever, differs  in  various  animals. 

Q.  Does  the  blood  always  preserve  the  same  den- 
sity ?  *  — A.  No.  Its  density  is  liable  to  great  variations, 
under  the  states  of  rest,  labor,  disease,  and  health. 

Q.  What  do  you  understand  by  the  "  crassamentum" 
of  the  blood?  —  A.  It  is  supposed  to  consist  chiefly 
of  fibrin. 

Q.  How  is  it  colored  ?  — A.  It  owes  its  peculiar  color 
to  what  is  termed  the  red  globules,  which  are  entangled 
in  it  during  its  coagulation. 

Q.  How  can  tliis  be  demonstrated? — A.  By  long 
continued  ablution  in  water,  the  red  particles  are  Uber- 
ated ;  and  we  have  remaining  a  wliite,  sohd,  and  elas- 
tic substance,  which  has  all  the  properties  of  fibrine, 
and  is  almost  exactly  similar  to  the  basis  of  muscle. 

Q.  By  what  name  was  fibrine  formerly  known  ?  —  A. 
Coagulable  lymph. 

Q.  What  is  the  form  of  the  red  globules  of  the 
blood? — A.  The  Abbe  de  la  Torre,  who  examined 
them  under  mici'oscopes  of  considerable  power,  states 
that  they  obtained  the  appearance  of  flattened  aimular 
bodies,  with  a  depression,  sometimes  perforation,  in  the 

*Dr.  B.  Babington  is  of  opinion  tliat  the  blood,  whilst  circulating 
in  the  vessels,  consists  of  two  parts  only  —  a  fluid  which  he  calls  liquor 
iaiig'i/inf.';,  and  red  globules;  and  he  is  induced  to  belieye,  from  his 
experiments,  that  fibrin  and  serum  do  not  exist  as  such  in  the  circu- 
lating fluid,  but  that  the  liquor  sanguinis,  when  removed  from  the 
vessels,  and  no  longer  subjected  to  the  laws  of  life,  has  then,  and  not 
before,  the  property  of  separating  into  fibrin  and  serum.  Med.  Chi- 
rvrg.  Transact,  vol.  xvi.  pt.  2.  Lond.  1831,  and  art.  Blood  (morbid 
conditions  of  the),  in  Cyclop,  of  Anat.  and  Physiol.  Lond.  1836. 


centre,  but  they  differ  in  size  and  shape  in  various 
animals. 

Q.  By  what  means  is  the  blood  colored?  —  A.  By 
means  of  iron  and  oxygen. 

Q.  Describe  the  properties  of  the  serum  ?  —  A.  It  is 
the  yellow  fluid  part  that  is  left  after  the  separation  of 
the  crassamentum ;  it  is  of  a  saline  taste,  and  homoge- 
nous, adhesive  consistence. 

Q.  What  effect  has  a  temperature  of  160°  on  it?  — 
A.  The  whole  is  converted  into  a  firm  white  mass,  per- 
fectly analagous  to  the  Avliite  of  an  egg  wliich  has  been 
hardened  by  boiling. 

Q.  Can  any  Hquor  be  extracted  from  the  serum  after 
having  been  coagulated  by  heat?  —  A.  Yes.  If  the 
coagulum  be  cut  into  slices,  and  subjected  to  gentle 
pressure,  an  opaque  liquor  di-ains  from  it,  which  is  called 
the  serosity. 

PERICAEDIUM. 

Q.  By  what  is  the  heart  surrounded?  —  A.  The 
pericardium. 

Q.  AVhat  is  the  structure  of  this? — A.  It  is  a  fibro- 
serous  membranous  bag,  composed  of  two  coats ;  one 
fibrous,  the  other  serous ;  these  are  miited  by  cellular 
tissue. 

Q.  AVhat  are  its  connections?  —  A.  It  is  attached  to 
the  sternum,  pleura,  diaphragm,  and  to  the  roots  of 
the  large  blood-vessels  at  the  base  of  the  heart. 

Q.  What  is  the  function  of  the  serous  surface  of  the 
pericardium? — A.  To  secrete  the  liquor  pericardii. 

Q.  What  is  the  use  of  this  Uquor  ?  —  A.  It  serves  to 
protect  its  own  sm-face,  and  that  of  the  heart,  from 
friction. 

Q.  What  oflice  does  the  pericardium  perform? — A. 
It  sustains  the  heart  in  its  proper  situation. 


THE   HOESE. 


157 


HEAKT. 

Q.  What  is  the  form  of  the  heart  ?  —  A.  Its  form  is 
conoid,  yet  somewhat  flattened  on  the  anterior  sm-face 
and  rounded  on  the  other. 

Q.  Where  is  the  heart  situated?  —  A.  Witliin  the 
thorax,  in  the  region  of  the  fourth,  fifth,  and  sixth 
dorsal  vertebrae ;  bounded  on  the  sides  by  the  limgs 
and  walls  of  the  thorax ;  posteriorly,  by  the  dia- 
phragm; inferiorly  and  anteriorly,  by  the  sternum. 

Q.  How  is  the  body  of  heart  divided  .^  —  A.  Into  a 
base  and  apex. 

Q.  What  are  the  divisions  internally  .►'  —  A.  It  is 
divided  into  four  cavities,  viz :  two  auricles,  or  anterior 
cavities ;  two  ventricles,  or  j^ostei'ior  cavities. 

Q.  What  communications  exist  between  the  cavities 
of  the  heart?  —  A.  Between  the  two  auricles  there  is 
no  communication,  nor  between  the  two  ventricles ; 
but  the  right  auricle  opens  into  the  right  ventricle,  and 
a  similar  opening  exists  between  the  left  amicle  and 
ventricle. 

Q.  How  do  veterinarians  describe  the  relative  situa- 
tion of  the  cavities  of  the  heart? — A.  The  amides  are 
described  as  anterior  and  posterior,  because  the  right 
auricle  forms  the  upper  and  fore  part,  and  the  left  is 
in  a  posterior  direction ;  the  ventricles  being  located 
imder  their  respective  auricles,-  thus  we  have  the  ante- 
rior and  posterior  ventricles. 

Q.  How  is  the  exterior  surface  of  the  heart  pro- 
tected ?  —  By  a  duphcature  of  the  pericardium. 

Q.  What  is  the  function  of  the  auricles? — A.  To 
receive  the  blood  from  the  various  vessels  and  transmit 
it  to  the  ventricles. 

Q.  What  is  the  function  of  the  ventricles?  —  A. 
One  propels  the  blood  to  the  lungs,  for  purification ; 
the  other  distributes  it  thi-cugh  the  arterial  ramifi- 
cations. 

Q.  Name  the  venous  vessels  wliich  terminate  in  the 
right  auricle.  —  A.  Three  venous  vessels  terminate  in 
it,  viz  :  the  vena  cava,  anterior  and  posterior,  and  the 
coronary  vein  j  the  vena  azygos  forms  a  junction  with 


the  anterior  cava,  just  as  the  latter  pierces  the  walls  of 
the  auricles. 

Q.  How  are  the  am-icles  di^ided  ?  —  A.  By  the  sep- 
tum auricularum. 

Q.  Describe  the  internal  mechanism  of  the  right 
ventricle?  —  A.  It  has  within  it  numerous  fleshy  pil- 
lars, longituchnally  distributed;  also,  three  fleshy 
prominences,  termed  carnea  columnae,  from  which  sev- 
eral tendmous  cords  proceed  to  the  edges  of  those 
membranous  and  fibrous  productions ;  these  close  the 
auriculo-ventrlcular  opening;  the  apparatus  alto- 
gether forms  valvula  tricupsis.  Other  cords,  similar  to 
the  cordae  tendinse,  pass  between  the  outer  wall  and 
the  septum. 

Q.  Where  is  the  origin  of  the  right  pulmonary  ar- 
tery?—  A.  It  emerges  from  the  upper  and  back  part 
of  the  ventricle. 

Q.  How  is  the  mouth  of  this  artery  protected  ?  —  A. 
By  three  semilunar  valves,  wiiich  present  little  pouches 
within  its  cavity ;  these  valves  consist  of  doublings  of 
the  lining  membrane  of  the  parts. 

Q.  Describe  the  left  ventricle? — A.  Its  cavity  is 
smaller  than  that  of  the  right,  and  its  wall  is  thicker. 
Its  musculi  pectinati  appear  mostly  upon  the  septum, 
within  the  apex  and  under  the  valves ;  it  has  two,  in- 
stead of  three,  carnse  columnae  ;  they  are  more  bulky, 
and  project  more  into  the  ca\ity  than  those  of  the 
right. 

Q.  From  whence  does  the  aorta  arise?  —  A.  From 
the  upper  and  fore  part  of  the  left  ventricle. 

Q.  What  is  remarkable  about  the  mouth  of  the 
aorta  ?  —  A.  It  has  thi-ee  semilmiar  valves,  similar  to 
those  at  the  origin  of  the  pulmonary  artery. 

Q.  By  what  are  the  ventricles  dinded  ?  —  A.  They 
are  divided  by  a  fleshy  joartition  called  septum  ventric- 
ulorum. 

Q.  How  is  the  circulation  of  the  blood  effected  ?  — 
A.  By  the  alternate  contraction  of  the  auricles  and 
ventricles,  called  the  dyastole  and  systole  of  the  heart. 

Q.  By  what  vessels  is  the  heart  itself  suppHed  with 
blood? — A.  By  the  coronary  arteries. 


ARTERIAL     SYSTEM. 


DISTRIBUTION    OF    ARTERIES. 

The  blood  is  propelled  by  the  heart 
through  the  gi-eat  aorta,  which  rises  out  of 
the  base  of  the  left  ventricle,  in  the  space 
between  the  left  auricle  and  the  pulmonary- 
artery.  The  branches  furnished  by  the 
main  trunk  are  the  coronary  arteries.  The 
right  coronary  artery  emerges  from  between 
the  pulmonary  and  right  auricle,  winds  round 
the  fissure  separating  that  cavity  from  the 
right  ventricle,  and  turns  down  under  the 
termination  of  the  vena  cava;  and  distri- 
butes ramifications  in  its  course,  which 
penetTate  the  substance  of  the  parietes, 
and  end  in  spiral  branches.  The  left  coro- 
nary artery,  in  passing  out  between  the 
pulmonary  artery  and  left  auricle,  sends 
off  a  large  branch,  which  encircles  the 
other  auricle ;  it  then  takes  its  course  down- 
ward, and  ends  in  spiral  ramifications. 

ANTERIOR   AORTA. 

This  is  a  shorter  division  of  the  main 
trunk.  The  course  of  this  vessel  is  under 
the  windpipe ;  it  gives  origin  to  those  large 
arteries  which  are  distributed  over  the 
breast,  head,  neck,  brain,  and  anterior  ex- 
tremities. It  divides,  at  a  short  distance 
from  the  heart,  into  the  right  and  left  ar- 
teria  innominata  ;  the  right  is  considerably 
longer  than  the  left,  and  measures  nearly  as 
much  again  in  circumference ;  it  forms  the 
trunk  from  which  the  two  carotid  arteries 
spring;  the  left  terminates  in  the  following 
vessels :  * 

1.  The  dorsal  artery.  2.  Posterior  cervi- 
cal. 3.  Vertebral.  4.  Internal  pectoral. 
5.  External  pectoral.     6.  Inferior  cervical. 

*  The  vertebral  artery,  forming  the  basilar,  gives  off 
the  posterior  cerebcllal,  anterior  cerebellal,  posterior  cere- 
bral, and  the  circular  arteriosus. 


7.  Axillary.  Each  of  these  arteries  ramify 
and  anastomose  with  others,  and  are  dis- 
tributed to  muscular  and  adipose  substance. 
From  the  axillary  artery  spring  all  the  ar- 
teries of  the  fore  extremity.  This  vessel 
can  only  be  seen  by  detaching  the  shoulder 
from  the  body.  It  arises  within  the  chest, 
from  the  arteria  innominata ;  gains  exit  by 
making  a  sudden  turn  around  the  first  rib, 
rather  below  its  middle,  crossing  the  lower 
border  of  the  scalenus  in  the  turn ;  it  is 
first  directed  outward  in  this  flexure,  and 
then  backward,  and  at  length  reaches  the 
inner  part  of  the  head  of  the  humerus, 
where  it  makes  another  turn  backward,  and 
afterwards  takes  the  name  of  the  brachial 
artery.  Its  branches  are  —  1.  The  external 
thoracic.  2.  The  internal  thoracic,  which 
runs  to  the  point  of  the  shoulder,  and  gives 
its  branches  to  the  levator  humeri  and 
shoulder  joint.  3.  The  dorsalis  scapula) 
ascends,  in  a  flexuous  manner,  to  the 
shoulder  joint,  crossing  the  insertion  of  the 
subscapularis.  It  runs  for  a  short  distance 
along  the  ribs.  4.  The  subscapularis,  a 
large  artery,  which  also  arises  from  the 
upper  part  of  the  trunk,  but  near  to  its  ter- 
mination. It  passes  along  the  ribs,  screened 
from  view  by  the  edges  of  the  subscapu- 
laris and  teres  major,  to  both  of  which 
muscles  it  detaches  several  small  branches, 
and  ends  near  the  lower  angle  of  the  bone ; 
it  also  gives  off  several  branches  to  the 
triceps  and  panniculus.     5.  The  humeral. 

The  humeral  artery  descends  from  the 
inner  and  back  part  of  the  head  of  the  os 
humeri,  in  an  oblique  direction  on  the  body 
of  the  bone,  where  it  divides  into  the  ulnar, 
spiral,  and  radial  arteries.  On  its  inner 
side,  it  has  the  spu'al  and  ulnar  ners^es  ;  in 
front,  the  radial  nerve;    and  behind,  the 

(158) 


ANATOMY  AND  PHYSIOL YGY  OF  THE  HORSE. 


159 


humeral  veins;  and  it  is  covered  inter- 
nally by  the  large  pectoral  muscle,  to  which 
it  sends  some  small  branches.  But  its  prin- 
cipal branches  are  —  1.  One  near  its  origin, 
which  crosses  the  bone  to  get  to  the  flexor 
brachii,  and  sends  twigs  to  the  shoulder- 
joint.  2.  A  posterior  branch,  arising  a  lit- 
tle lower  down,  which  enters  the  muscle 
called  triceps.  3.  Near  its  termination, 
another  branch  to  the  flexor  brachii.  Where 
the  artery  divides,  it  is  covered  by  the  hu- 
meral plexus  of  veins,  and  by  the  absorbent 
glands  of  the  arm. 

The  ulnar  artery  consists  of  a  common 
root,  from  which  spring  three  or  four  ves- 
sels of  considerable  size,  running  in  waving 
lines  upon  the  inner  side  of  the  lower  end 
of  the  humerus.  The  upper  one  is  directed 
to  the  ulnar,  splitting  before  it  reaches  the 
bone,  and  sending  one  branch  upward  upon 
the  elbow,  and  another  downward  to  the 
heads  of  the  flexors ;  to  which  muscles 
the  other  branches  of  this  vessel  are  dis- 
tributed. 

The  spiral  artery,  the  outermost  division, 
turns  round  the  os  humeri,  passing  under 
the  flexor  brachii,  and  sending  a  recurrent 
branch  to  it,  to  arrive  at  the  front  of  the 
radius,  where  it  splits  into  several  branches, 
of  which — 1.  Some  run  into  the  elbow 
joint.  2.  Others,  larger  and  more  numer- 
ous, penetrate  the  heads  of  the  extensors. 
3.  Two  long,  slender  ones  descend  upon  the 
radius,  and  give  branches,  in  their  course, 
to  the  extensor  muscles  as  low  as  the  knee, 
and  there  end  in  ramifications  about  and 
into  the  joint,  joining  with  others  coming 
from  the  radial. 

The  radial  artery,  the  principal  division 
humeral,  continues  its  descent  along  the 
radius,  about  the  middle  of  the  arm  ;  the 
nerve  accompanies  it  first  on  its  outer  side, 
and  subsequently  behind  it.  A  short  way 
above  the  knee,  it  splits  into  the  metacarpal 
arteries. 

The  small  metacarpal  artery  descends, 
within  a  cellular  sheath,  along  the  inner  and 
back  part  of  the  knee.  It  continues  its 
descent  along  the  metacarpal  vein  (which 
runs  to  its  inner  side),  till  it  gets  below  the 


knee,  and  then  transmits  its  divisions  down 
the  front  of  the  suspensary  ligament;  be- 
tween it  and  the  canon  bone,  it  sends  off" 
branches  over  the  front  of  the  knee,  the 
canon,  and  suspensary  ligament. 

The  large  metacarpal  artery,  a  continua- 
tion of  the  radial  trunk,  continues  its  course 
down  the  leg,  by  the  side  of  the  tendo  per- 
foratus,  passing  under  the  posterior  annular 
ligament,  approaches  the  fetlock  just  above 
the  joint,  and  then  splits  into  three  vessels ; 
from  the  middle  division  three  recurrent  ar- 
teries are  given  out ;  the  side  divisions  be- 
come the  plantar  arteries.  From  the  arch 
below  come  off"  two  other  branches,  which 
descend  into  the  joint.  The  plantar  arte- 
ries, external  and  internal,  in  the  fore  ex- 
tremity, result  from  the  fork  of  the  meta- 
carpal ;  in  the  hind,  from  that  of  the 
metatarsal.  (Then*  general  distribution  is 
the  same,  both  in  the  hind  and  fore  feet.) 
They  descend  the  fetlock  upon  the  sides  of 
the  sessamoids,  in  company  with  the  veins 
which  run  in  front  of  them,  and  with 
the  plantar  nerves  which  proceed  behind 
them  ;  the  artery  then  passes  down  to, 
and  into,  the  substance  of  what  is  called 
the  "  fatty  frog  ; "  it  next  passes  the  inner 
and  upper  extremity  of  the  coffin  bone,  and 
afterwards  to  the  foramen  of  the  posterior 
concavity  of  the  bone.  The  branches  of 
the  plantar  artery  are  many  and  important. 
After  detaching  some  small  ramifications 
inwardly  to  the  fetlock,  posteriorly  to  the 
flexor  tendons,  and  anteriorly  to  the  ex- 
tensor tendon,  it  then  sends  off" — 1.  The 
perpendicular  artery.  2.  The  transverse 
artery.  3.  The  artery  of  the  frog.  4.  The 
lateral  laminal  artery.  5.  The  cu'culus  ar- 
teriosus. From  the  latter  arise  two  prin- 
cipal sets  of  vessels  —  1.  The  anterior 
laminated  arteries.  2.  The  inferior  com- 
municating arteries,  "thirteen,  and  some- 
times fourteen,  in  number."  3.  The  circum- 
flex artery.  Then,  again,  from  this  vessel 
spring  the  solar  arteries,  which  may  be  so 
named  from  their  radiated  arrangement. 
These  latter  are  destined  for  the  supply  of 
the  sole,  upon  which  they  run  in  radii  at 
equal  distances,  whose  common  centre  is  the 


160 


ANATOMY   AND   PHYSIOLOGY   OP 


toe  of  the  frog,  where  they  end  in  commu- 
nications with  the  arteries  of  that  body. 

THE    CAROTID    ARTERY. 

The  right  arteria  innominata,  having  de- 
tached seven  important  branches,  which 
vary  but  little  in  their  mode  of  origin, 
general  course,  and  distribution,  from  the 
several  arteries  into  which  the  left  division 
resolves  itself,  become  the  common  carotid 
—  a  large  vessel  emerging  through  the  up- 
per opening  of  the  chest ;  it  divides,  as  it 
quits  the  chest,  into  t\vo  branches,  called 
the  right  and  left  carotids.  These  arteries 
ascend,  and  having  reached  the  top  of  the 
lEirynx,  the  carotid  of  either  side  branches 
into  three  divisions — the  external  and  inter- 
nal carotids,  and  the  ramus  anastomoticus : 
here,  though  the  trunk  itself  becomes  deeply 
lodged  in  soft  parts,  its  situation  is  well  in- 
dicated by  the  larynx,  with  which  it  is  in 
contact.  This  vessel  detaches — 1.  Several 
unimportant  muscular  branches  in  its  pro- 
gress up  the  neck.  2.  The  thyroideal 
artery,  which  furnishes  the  laryngeal,  a 
small  artery  that  perforates  the  ligament 
uniting  the  cartilages  of  the  throat. 

The  external  carotid  artery  is  the  large 
division,  which  may  be  regarded  as  the  con- 
tinuation of  the  carotid  itself.  This  artery 
is  imbedded  in  glandular  substance,  sur- 
rounded by  venous  and  nervous  trunks,  and 
protected  by  bony  prominences  and  muscles. 
The  first  branch  of  the  external  carotid  is 
the  submaxillary  artery ;  it  comes  off  behind 
the  horn  of  the  ox  hyoides,  just  as  the 
carotid  makes  its  second  curve,  and  ranks 
next  in  size  to  the  trunk  itself.  After  reach- 
ing the  lower  jaw  (about  one-third  of  its 
length  downwards),  it  arrives  upon  the  face; 
here  it  becomes  subcutaneous,  ending  in  an 
equal  division,  called  the  facial  and  inferior 
labial  arteries.  Its  branches  are,  the  ascend- 
ing laryngeal,  pharyngeal :  smaller  branches 
go  to  parotid  gland,  and  a  large  branch, 
called  the  lingual.  The  latter  detaches  a 
few  twigs  into  the  submaxillary  space ;  it 
then  branches  into  two  arteries,  the  ranine 
and  the  subhngual.  The  ranine,  apparently 
a  continuation  of  the  lingual,  passes  along 


the  under  part  of  the  tongue,  and  transmits 
branches  to  the  interior,  and  continues  of 
large  size  even  to  the  tip  of  the  orgp^n, 
wherever  its  extreme  ramifications  are  ex- 
pended. The  sublingual  artery  winds  along 
the  under  and  outer  border  of  the  tongue, 
preserving  a  more  superficial  course  than 
the  former.  It  supplies  the  sublingual 
gland,  and  distributes  branches  over  the 
membrane  of  the  tongue.  The  submental 
artery  leaves  the  submaxillary,  follows  the 
course  of  the  branch  of  the  jaw,  and  de- 
taches twigs  to  muscles ;  it  then  transmits 
its  ramifications  into  the  gums  internally. 
The  anterior  masseter  branches  pass  on  the 
external  side  of  the  jaw. 

The  infet'ior  labial  artery  courses  the  side 
of  the  jaw,  invested  in  the  cellular  and 
fleshy  substance  belonging  to  the  buccinator. 
It  gives  off  slender  ramifications  to  the  in- 
vesting cellular  substance,  also  the  buc- 
cinator arteries ;  the  buccal  twigs  bifurcate, 
sending  their  divisions  respectively  to  the 
upper  and  under  lips  ;  these  form  the  supe- 
rior and  inferior  coronary  arteries  of  the  lips. 

The  facial  artery  ascends  upon  the  side 
of  the  face,  crosses  the  buccinator,  then, 
having  run  as  high  as  the  bony  ridge  from 
whence  the  masseter  arises,  it  detaches  a 
large  branch,  and  then  expands  upon  the 
upper  and  fore  part  of  the  face ;  its  termi- 
nating ramifications  are  in  the  cellular  sub- 
stance and  skin  covering  the  fore  part  of 
the  face. 

The  posterior  auricular  gives  branches  to 
the  parotid  gland,  and  to  the  different  mus- 
cles of  the  ears. 

The  temporal  artery ^\h&  anterior  auricular, 
and  the  internal  maxillary,  may  be  con- 
sidered as  the  terminating  branches  of  the 
external  carotid.  The  internal  maxillary 
gives  off  deep  temporal  branches,  long 
slender  twigs,  to  the  soft  palate,  to  the  ear, 
and  to  the  articulation  of  the  jaw;  the  facial 
artery  also  gives  off  the  inferior  maxillary, 
the  supra-orbitar,  the  ocular,  the  infra- 
orbitar,  and  the  palate  maxillary.  The 
second  and  smallest  division  of  the  carotid 
is  the 


EXPLANATION   OF   FIGURE  XVL 


NO.    1. 

FROKT  AND   SIDE   \TEAV  OF   THE  NEAH-HIND  LEG. 


g.     Ligaments  of  the  patella. 

J".  Tricejjs. 

m\  Tensor  vagina. 

n\    Rectus. 

o'.    Vastus  externus. 

q".  y\  Extensor  suffiaginis. 

X.  X.  Extensor  pedis. 

7.  Sheath  and  penis. 

8.  Bifurcation  of  the  suspensorj'  ligament. 
Sr.    The  hoof. 


NO.   2. —  OSSEOUS   STRUCTURE. 


22. 

Femur. 

23. 

Patella. 

24. 

Tibia. 

e. 

Fibula. 

25. 

Os  calcis. 

26. 

Astragalus. 

27. 

Inferior  tarsus. 

28. 

Metacarpus  magnum. 

* 

"           par\Tas. 

29. 

Sessamoids. 

30. 

Os  suffi'aginis. 

31. 

Os  corona. 

32. 

Os  pedis. 

NO.    3. 

OUTSIDE   VIEW    or   THE   NEAR-HIND  LEG. 

K.   Abductors. 

J".  Triceps. 

m'.  Tensor  vagin^. 

rrC.  Rectus. 

o'.  Vastus  externus. 

r'.    Gastrocnemius  externus. 

V.  s\  Peroneus. 

«'.  Gastrocnemius  externus. 

«'.  u\  Flexor  pedis. 

X.   Extensor  pedis. 

y.  y.  Extensors. 

II.  V.  Flexor  tendons. 

^.   The  hoof. 

8.    Bifurcation  of  suspensory  ligament. 

No.  4  is  nearly  the  same  as  No.  3,  and  therefore  needs  no  further  descrii)tion. 
z.     Suspensory  Hgament. 


162 


ANATOMY  AND   PHYSIOLOGY   OP 


into  the  right  and  left  hepatic ;  the  right, — 
the  larger  and  shorter  one,  —  after  giving  off 
a  considerable  branch  to  the  portio  media, 
turns  back  to  reach  the  right  lobe  ;  the  left, 
after  giving  off  a  branch  or  two  to  the  mid- 
dle portion,  penetrates  the  left  lobe. 

The  anterior,  or  great  mesenteric,  is  the 
next  vessel  to  the  coeliac,  and  arises  from 
the  under  part  of  the  posterior  aorta.  From 
its  origin,  it  passes  downward  Avithin  the 
layers  of  the  mesentery,  detaching  some 
small  twigs  to  the  pancreas ;  it  then  sepa- 
rates into  larger  vessels  (commonly  from 
eight  to  twelve  in  number),  from  which  are 
derived  a  branch  that  runs  to  the  duode- 
num ;  several  other  branches  encircle  and 
ramify  on  and  around  the  intestines. 

The  renal  or  emulgent  artsries  leave  the 
aorta  at  right  angles  just  below  the  preced- 
ing vessel ;  they  each  pass  into  the  respect- 
ive kidneys,  and  therein  divide  into  branches 
that  penetrate  the  glandular  substance. 

The  spermatic  arteries,  right  and  left, 
originate  from  the  under  part  of  the  aorta ; 
they  pass  out  of  the  abdomen,  at  the  ab- 
dominal ring,  to  the  testicles.  In  the  female, 
they  pass  to  the  ovaries,  fallopian  tubes, 
and  horns  of  the  uterus. 

The  posterior  aorta  also  gives  off  the 
small  mesenteric,  and  five  or  six  pairs  of 
lumbar  arteries.  Under  the  last  lumbar 
vertebrae,  the  aorta  gives  off  two  pairs  of 
arterial  trunks,  called  the  external  and  inter- 
nal iliacs. 

The  internal  iliacs  give  off  a  branch 
called  the  artery  of  the  bulb,  and  afterwards 
branches  into  three  divisions  —  the  obtura- 
tor, gluteal,  and  lateral  sacral  arteries. 

The  artery  of  the  bulb  passes  to  the  bulb 
of  the  penis,  where  it  terminates.  In  the 
female,    this    artery  sends    its   terminating 


branches  to  the  vagina. 


It   gives  off  the 


foetal  umbilical  artery.  In  leaving  the  pel- 
vis, the  prostatic  artery,  which  detaches 
twigs  to  the  vesiculsB  seminales,  also  distri- 
butes its  ultimate  ramifications  to  the  pros- 
tate gland.  It  also  gives  off  divers  branches, 
anal  and  perineal,  to  the  posterior  portion 
of  the  rectum,  anus,  and  parts  comprising 
the  perineum. 


The  obturator  artery  is  the  lowest  of  the 
divisions^  of  the  internal  iliac.  Its  branches 
are  tlie  arteria  innominati,  and  ramifications 
to  the  obturator  muscles  and  ligaments.  Its 
divisions  are  the  ischiatic,  which  distributes 
its  branches  to  the  triceps  ;  next,  the  pubic : 
the  internal  pubic  artery  gives  two  sets  of 
branches,  which  pass  to  the  penis. 

The  gluteal  artery  is  destined  principally 
to  supply  the  gluteal  muscles. 

The  lateral  sacral  artery,  having  reached 
the  coccyx,  divides  into  two  branches.  It 
furnishes  the  sacro-spinal  branches,  five 
or  six  in  number,  and  the  perineal  artery. 
It  soon  divides  into  several  ramifications, 
of  which  many  run  into  the  gluteal  mus- 
cles ;  others  descend  on  the  back  of  the 
thigh,  and  others  are  distributed  to  the  anal 
muscles,  and  to  the  skin  and  cellular  sub- 
stance of  the  perineum.  The  lateral  sacral 
also  furnishes  the  lateral  coccygeal,  and 
the  inferior  coccygeal. 

The  external  iliac  artery,  right  and  left, 
results  from  a  branch  of  the  posterior  aorta, 
which  takes  place  under  the  body  of  the 
last  of  the  lumbar  vertebrae,  and  passes 
into  muscles,  forming  the  inside  of  the 
thighs.  The  vessel  gives  off  the  circumflex 
artery  of  the  ileum,  the  artery  of  the  cord, 
and  the  arteria  profunda :  the  latter,  having 
reached  the  posterior  quarters,  it  sends  its 
ramifications  into  the  biceps.  Before  this 
vessel  dips  into  the  substance  of  the  thigh, 
it  gives  rise  to  a  large  branch  called  the 
epigastic  artery. 

The  eptg-astric  artery,  in  passing  the  mar- 
gin of  the  internal  ring,  forms  a  branch 
which  divides  into  several  small  arteries ;  of 
these  a  twig  runs  to  the  groin,  and  ramifies 
among  the  adipose  membrane  and  absorbent 
glands ;  then,  next,  a  slender  branch  to  the 
cremaster,  and  subcutaneous  twig  to  the 
thigh,  and,  lastly,  the  external  pudic  artery. 

The  femoral  artery. — Regarding  the  pro- 
funda femoris  as  a  limb  of  the  external 
iliac,  we  descend  to  the  femoral  artery,  the 
subsequent  continuation  of  the  same  trunk. 
This  artery  proceeds  in  an  oblique  direction 
down  the  haunch,  preserving  nearly  the  line 
of  its  middle ;   opposite  to  the  head  of  the 


THE   HORSE. 


163 


tibia,  it  branches  into  the  ^anterior  and  pos- 
terior tibial  arteries ;  the  anterior  tibial  gives 
off  the  inguinal  artery,  also  three  or  four 
branches  to  the  sartorius,  and  one  to  the 
side  and  front  of  the  stifle.  Its  posterior 
branches  are  a  large  artery  to  the  gracilis 
(which  detaches  twigs  to  the  long  and  short 
heads  of  the  triceps),  also  one  to  the  biceps. 
At  the  back  of  the  stifle  come  off  the  pop- 
liteal branches,  four  or  five  in  number, 
taking  opposite  directions,  wliich  are  des- 
tined for  the  supply  of  the  joint ;  one  runs 
down  upon  the  posterior  tibial  muscles; 
another — the  recurrent  branches — climbs 
the  back  of  the  os  femoris,  and  anastomoses 
with  the  descending  ramifications  of  the 
profunda  femoris. 

The  tibial  arteries  are  a  continuation  of 
the  femoral  trunk,  which  branch  off  into 
tibial  arteries  at  the  head  of  tibia. 

The  posterior  tibial  artery^  the  smaller  of 
the  two,  passes  along  the  posterior  deep 
region  of  the  thigh,  to  the  hock,  where  it 


ends  in  bifurcation.  Its  branches  are,  one 
that  runs  into  the  flexor  pedis ;  another  to  the 
upper  and  back  part  of  the  tibia ;  and  small 
twigs  to  both  the  flexors.  There  are  several 
terminating  branches,  some  ramifying  sub- 
cutaneously,  others  continuing  down  the  leg 
internally  over  the  tendon  of  the  flexor 
pedis,  and  ending  at  the  lower  part  of  the 
canon  in  divers  smaU  ramifications. 

The  anterior  tibial  artery,  after  leaving 
the  trunlv,  passes  down  the  fore  part  of  the 
thigh  to  the  hock  and  metatarsal  bone, 
where  it  becomes  the  metatarsal  artery. 

The  metatarsal  artery  pursues  its  course 
downwards  to  about  two-thirds  the  length 
of  the  leg ;  it  then  gains  the  posterior  part 
of  the  latter ;  a  little  above  the  fetlock,  it 
divides  into  three  vessels :  one  forms  an  arc, 
(as  in  the  fore  extremity),  from  which  come 
off  the  recurrents,  and  they  anastomose 
with  the  posterior  tibial  artery ;  the  lateral 
divisions  become  the  plantar  arteries. 


164 


ANATOMY    AND   PHYSIOLOGY   OF 


REMARKS  ON  THE  DISTRIBUTION  OF  ARTERIES. 

The  preceding  is  a  brief  sketch  of  the  arterial  structure,  and  the  professional  man 
will  perceive  that  wc  have  not  named  the  whole  of  the  arteries  ;  therefore,  in  order  to 
supply  this  deficiency,  the  author  here  introduces  a  table  of  the  arteries,  constructed  by 
Mr7  Percivall. 


Aorta 


Anterior  Aorta 


Left  Arteria 
Innominata 


table  of  the  arteries. 
Anterior  Aorta. 
Posterior  Aorta. 
Right  Arteria  Innominata. 
Left  Arteria  Innominata. 
'^Dorsal. 
Posterior  Cervical. 
Vertebral,  forming  the  Basilar. 
Internal  Pectoral. 
External  Pectoral. 
Inferior  Cervical. 
Axillary. 

f^  External  Thoracic. 
Internal  Thoracic. 
Axillary  <  Dorsalis  Scapula. 
Subscapular. 
Humeral. 
f  Ulnar. 


/'Posterior  Cerebellal. 
1  Anterior  Cerebellal. 
I  Posterior  Cerebral. 
(^Circular  Arteriosus. 


TT  1  J  Spiral 

Humeral  <  -  ^ 


Radial. . .    (  Small  Metacarpal. 

I  Large       ditto. 

T  T»/r  J-  ^  \  External  Plantar. 

Large  Metacarpal  j  j^^^^^.^^^j     ^.^^^^ 

'  Perpendicular. 
Transverse. 
Plantar  <  Artery  of  the  Frog. 

Lateral  Laminal.  (  Ant.  Laminal. 

^  Circular  Arteriosus. . .  <  Inf.  Communicating. 

(  Circumflex.  .  .  .  <(  Solar. 

The  Right  Arteria  Innominata  sends  off  branches  correspondent  to  those  on  the  left 
side;  and,  in  addition,  the 

Right  Carotid  1  External  Carotid. 
Left      ditto.     >  Ramus  Anastomoticus. 
)  Internal  Carotid. 
^  Ascending  Pharyngeal. 


Common  Carotid 


External  Carotid  < 


Submaxillary. 


Parotideal. 
Int.  Pterygoid. 
Post.  Masseter. 
Post.  Auricular. 
Temporal. 
Ant.  Auricular. 
Int.  Maxillary. 


Pterygoid. 
Lingual.    .    . 

Inferior  Labial. 


Facial. 


Ranine. 
Sublingual. 
Buccinator. 
Angular  Oral. 

{Masseter. 
Buccal. 
Sup.  Labial. 
False  Nasal. 


''Deep  Temporal. 

Palatine. 

Inf.  Maxillary. 
<(  Supra- Orbitar. 

Ocular. 

Infra- Orbitar. 

Palato  Maxillary. 


1 


THE   HORSE. 


165 


!(  Dura  Matral. 
Occipital.    \  Temporal. 
(  Nuchal. 
fArteria  Communicans. 
Anterior  Dura  Matral. 
Anterior  Cerebral.  .  .  •{  Ophthalmic 
Middle  Cerebral. 
Lateral  Cerebral. 


Internal  Carotids 


Posterior  Aorta 


Thoracic  Division  <J  Esophageal. 
Intercostals. 


Thoracic  Division. 
Abdominal  ditto. 

Right  Bronchial. 

Left         ditto. 

Superior  Esophageal. 

Inferior        ditto. 


Bronchial 


Phrenic. 


Abdominal 
Division 


Cselic   < 


Splenic 
Gastric 


Hepatic 


Anterior  Mesentric 


Pancreatic  Branches. 

Splenic  Branches. 

Left  Gastric. 

Superior  Gtistric. 

Inferior      ditto. 
'  Pancreatic  Branches. 

Duodenal. 

Right  Gastric. 

Right  and  Left  Hepatic. 
'Duodenal  Branches. 

Small  Mesenteric. 

Coecal  Branches; 

Anterior  Colic  Branches. 


Branches. 


I  Right  Renal.  )  External  Brand 

^6^^^ \  Left    ditto.    ]  Capsular  Renal 

Spermatic  <(  Right  and  Left. 

Posterior  Mesenteric    |  ^eftar"" 
Lumbars  —  five  or  six  pairs. 

Bifurcation  of  the  Posterior  Aorta  into  External  and  Internal  Iliac  Arteries. 


Internal  . 
Iliac.    ^ 


Artery  of  the  Bulb 


Obdurator 


'  Umbilical. 
Vesical  Branches. 
Prostatic. 

Anal  and  Perineal  Branches. 
Arteria  Innominata. 
Foraminal  Branches. 
Ischiatic. 

'  Branches  to  the  Crus  Penis. 
Pubic  Ditto  Corpus  Cavernosurn. 

Int.  Pubic   -!  Ditto  Dorsum  Penis'. 
Ditto  Glans  Penis.' 
Cutaneous  Brandies. 


The  Middle  Sacral  issues  at  the  Bifurcation  of  the  Trunk. 

Circumflex  of  the  Ileum. 

Artery  of  the  Cord.  (  Branch  to  the  Grom. 

Arteria  Profunda.  -{  Epigastric. 


External  Hiac 


Branch  to  the  Ring. 


Femoral. 


External  Pudic' 


166 


ANATOMY   AND   PHYSIOLOGY   OF 


Femoral 


Inguinal. 

INIuscular  Branches. 
Stille  Branches. 
Muscular  Branches. 
Popliteal.  -{  Recurrent. 


Anterior  Tibial 


Posterior  Tibia 


Recurrent  Articular. 

Muscular  Branches. 

Cutaneous  Branches. 

Metatarsal  Branches. 

Metatarsal  Artery.    . 

Muscular  Branches. 

Medullary. 

Tarsal. 

Internal  Metatarsal.  -\  Recurrent. 


Recurrent. 
External  Plantar. 
Internal  Plantar. 


DISTRIBUTION   OF   VEINS   IN 
THE    HORSE. 

The  two  main  venous  trunks,  the  vence 
cavce,  anterior  and  posterior,  correspond  to 
the  anterior  and  posterior  aortse. 

THE    ANTERIOR    VENA    CAVA 

Forms  the  main  trunk  of  the  veins,  re- 
turning the  blood  from  the  head,  neck,  chest, 
and  fore  extremities.  It  is  principally  formed 
by  the  concurrent  union  of  the  jugular  and 
axillary  veins,  and  is  situated  at  its  forma- 
tion in  the  space  between  the  two  first  ribs, 
about  midway  between  the  sternum  and 
vertebraj ;  it  also  receives  the  pectoral,  ver- 
tebral, dorso-cervical,  and  inferior  cervical 
veins,  and  the  vena  azygos. 

THE    JUGULAR    VEIN. 

It  passes  behind  the  condyle  of  the  lower 
jaw,  under  the  parotid  gland,  and  joins  the 
external  carotid  artery,  and  continues  its 
course  down  the  neck  with  the  latter.  It 
now  receives  the  auricular  veins,  anterior 
and  posterior,  and  also  internal.  The  next 
is  the  temporal,  the  third  is  the  internal 
maxillary ;  the  latter  in  its  course  receives 
the  blood  of  many  small  veins, — the  palato- 
maxillary, infra  and  supra  orbitar,  ocular, 
inferior  maxillary,  and  deep  temporal ;  the 
fourth  branch,  received  by  the  jugular  vein, 
is  the  parotideal,  and  the  last  branches  from 
the  masseter  muscles. 

THE    OCCIPITAL    VEIN 

Descends  from   the   head,  along  with  the 


occipital  artery.  It  brings  blood  from  the 
occipital  sinuses,  receives  veins  from  the 
posterior  lobes  of  the  cerebrum  and  cere- 
bellum ;  also  from  the  dura  mater. 

The  submaxillar?/  vein  is  a  large  branch  of 
the  jugular.  It  is  formed  upon  the  side  of 
the  face  by  the  concurrence  of  the  facial, 
labial,  and  varicose  veins.  It  joins  the 
trunk  by  the  side  of  the  trachea,  just  below 
the  parotid  gland.  In  its  course  it  receives 
a  number  of  veins ;  the  principal  are  —  the 
submental,  sublingual,  lingual,  pharyngeal, 
and  superior  laryngeal  veins.  The  facial 
vein  results  from  an  expansion  of  small 
veins  upon  the  side  of  the  face,  one  of 
which  is  the  varicose  from  the  masseter. 
The  labial  vein  is  formed  by  the  union  of 
a  plexus  of  venous  branches,  coming  prin- 
cipally from  the  angle  of  the  mouth,  joined 
by  others  both  from  the  upper  and  lower 
lips.  The  varicose  vein  is  buried  in  the 
masseter. 

The  jugular  trunk  having  received  the 
submaxillary,  proceeds  down  the  neck,  and 
terminates  in  the  anterior  vena  cava,  within 
the  space  between  the  two  first  ribs.  Near 
the  junction  of  the  submaxillary  the  jugu- 
lar receives  the  small  thyroideal,  cutaneous, 
muscular,  and  tracheal  veins.  Near  its 
termmation  it  receives  a  branch  of  the 
superficial  brachial,  and  plait  or  plat  vein. 

The  vertebral  vein  runs  the  same  course 
as  the  artery,  through  the  foramina,  in  the 
transverse  processes  of  the  cervical  verte- 
bras, with  the  exception  of  the  last.     This 


THE    HORSE. 


167 


vein  has  communications  with  the  occipital 
sinus  and  posterior  cerebral  veins,  medulla 
oblongata,  and  spinal  marrow ;  it  also  re- 
ceives vessels  from  the  deep-seated  mus- 
cles in  the  vicinity,  and  ends  in  the  an- 
terior vena  cava,  just  behind  the  first  rib. 

The  axillary  vein  returns  the  blood  dis- 
tributed by  the  axillary  artery  to  the  va- 
rious parts  of  the  fore  extremity  ;  there  is  a 
superficial  and  deep-seated  set;  the  former 
run  under  the  skin,  the  latter  among  the 
muscles.  The  plantar  veins  are  an  intri- 
cate network  of  small  veins,  and  cover  the 
foot  with  a  venous  netting.  The  veins 
of  the  sole  pour  their  blood  into  the  veins 
of  the  lamina ;  the  latter  increase  in  size 
towards  the  coronet,  and  gradually  unravel 
themselves,  so  as  to  collect  in  a  great  many 
branches ;  these  run  upward,  through  the 
substance  of  the  coronary  ligament,  and 
form  the  superficial  coronary  vein ;  from 
them  other  branches  proceed  and  join  the 
deep  coronary,  and  afterwards  unite  in 
a  single  vein  opposite  the  pastern  joint. 

The  veins  of  the  frog,  after  ramifying  in 
the  form  of  network  over  that  body,  ascend 
into  the  heel,  growing  larger  as  they  leave 
the  foot ;  they  make  a  single  branch  at  the 
pastern  joint,  then  unite  with  the  vein  com- 
ing from  the  laminae,  thereby  forming  the 
plantar  vein.  The  plantar  vein  ascends, 
unites  with  other  vessels,  and  becomes 
metacarpal. 

The  metacarpal  veins,  two  in  number, 
result  from  the  union  of  the  plantar  ;  these 
veins  pursue  their  course  up  the  leg,  one  on 
either  side,  to  the  back  of  the  knee,  where 
they  end  in  anastomosis.  The  internal 
metacarpal  vein  preserves  the  line  of  the 
splint  bone.  These  vessels  receive  in  their 
course  cutaneous  veins  from  the  front  of 
the  canon,  and  one  or  two  descending 
veins  from  the  back  of  the  leg;  it  after- 
wards forms  the  deep-seated  veins  of  the 
arm. 

The  superficial  brachial  vein  ascends 
along  the  inner  side  of  the  radius  to  the 
elbow-joint ;  here  it  crosses  over  to  the  front 
of  the  biceps  and  pursues  its  ascent  upon 
that  muscle  toward  the  point  of  the  shoul- 


der, and  then  passes  inward  to  the  jugular 
vein.  In  its  course  to  the  latter,  it  receives 
numerous  cutaneous  and  muscular  branches, 
communicates  with  the  humeral  vein,  and 
anastomoses  with  other  veins  of  the  arm. 

The  radial  veins,  two  in  number,  arise 
from  the  junction  of  the  metacarpal  veins 
above  the  knee ;  they  take  the  course  of 
the  radial  artery,  and  receive  anastomosing 
vessels  as  they  ascend  from  the  ulnar  and 
superficial  veins. 

The  ulnar  veins  (with  one  exception) 
end  in  the  common  trunk  of  the  humeral 
vein. 

The  humeral  vein  accompanies  the  ar- 
tery ;  it  receives  small  veins  from  the  mus- 
cles. 

The  axillary  vein  is  the  continuation  of 
the  humeral,  augmented  by  the  accession 
of  the  triceps  vein.  Its  branches  are,  the 
subscapular  vein,  and  dorsalis  scapular; 
the  latter  terminates  about  midway  be- 
tween the  chest  and  shoulder.  The  re- 
maining branches  of  this  vein  are  the 
humeral  thoracic,  and  the  external  thoracic  ; 
it  also  receives  other  small  veins,  which 
contribute  more  or  less  to  its  volume. 

The  pectoral  vein  runs  the  course  of  the 
pectoral  artery.  It  originates  in  branches 
from  the  abdominal  parietes,  continues  to 
receive  accessory  vessels  in  its  course,  and 
ascends  along  the  inner  and  lower  border 
of  the  first  rib. 

The  dorso-cervical  vein  consists  of  two 
divisions,  ramifying  with  the  dorsal  and 
posterior  cervical  arteries;  it  receives  the 
anterior  intercostal  vein. 

The  inferior  cervical  vein  runs  down  the 
lower  part  of  the  neck  in  company  with  the 
artery ;  the  principal  branches  are  muscular, 
though  some  come  from  the  sldn  and  ab- 
sorbent glands  in  the  vicinity. 

The  vena  azygos  ends  just  as  the  trunk 
opens  into  the  auricle  ;  it  retm-ns  the 
blood  from  the  lower  intercostal  veins.     • 

THE    POSTERIOU    VENA    CAVA. 

This  is  the  corresponding  venous  trunk 
to  the  posterior  aorta,  returning  the  blood 
from  the  parietes  of  the  abdomen  and  pel- 


168 


ANATOMY   AND   PHYSIOLOGY   OF 


vis,  the  urinary  and  genital  organs,  and  the 
posterior  extremities.  It  takes  its  course 
under  the  bodies  of  the  lumbar  vertebraB, 
runs  along  the  great  fissure  of  the  liver, 
perforates  the  cordiform  tendon,  and  pur- 
sues its  way  directly  across  the  cavity  of 
the  chest  to  the  lower  part  of  the  right  auri- 
cle :  in  its  passage  it  is  joined  by  the  lum- 
bar spermatic,  renal,  hepatic,  and  diaphragm- 
atic veins. 

The  common  iliac  veins  are  formed  under 
the  sacro-iliac,  symphysis,  by  the  union  of 
the  external  and  internal  iliacs  ;  they  re- 
ceive a  vein  from  the  psoas  and  iliacus,  cir- 
cumflex vein  of  the  ileum,  middle  sacral, 
and  azygos. 

The  ischiatic  vein,  situated  upon  the  side 
of  the  pelvic  cavity,  midway  between  the 
external  iliac  and  lateral  sacral  veins ;  ex- 
ternal and  internal  branches  unite  to  form 
it.  The  internal  comprise  veins  coming 
from  the  bladder,  anus,  perineum,  and,  in 
the  male,  from  the  bulb  and  prostate:  in 
the  female,  from  the  vulva  and  body  of  the 
vagina.  The  external  come  principally 
from  the  gluteal  and  obturator  muscles. 

The  lateral  sacral  vein  comes  from  the 
tail,  formed  by  coccygeal  veins ;  it  runs 
forward  to  the  sacrum,  and  receives  in 
its  course  the  perineal  and  sacro-spinal 
branches. 

The  external  iliac  vein  takes  the  same 
course  as  the  artery ;  as  it  departs  from  the 
belly,  this  vessel  receives 

The  inguinal  vein  (coming  from  the 
groin),  also  a  superficial  or  cutaneous 
abdominal  vein,  known  as  the  milk  vein  in 
cattle. 

The  femoral  vein  is  the  continuation  of 
the  iliac  trunk  below  the  brim  of  the  pelvis ; 
and  is  the  main  channel  into  which  the 
deep-seated  veins   of   the   hind   extremity 


pour  their  blood.  We  commence  the  de- 
scription, as  in  the  fore  extremities,  at  the 
leg. 

The  large  metatarsal  vein  ascends  the 
canon  by  the  side  of  the  flexor  tendons, 
and  passes  over  the  front  and  inner  part  of 
the  hock ;  it  sends  out  branches,  from  which 
result  the 

Anterior  tibial  veins,  which  run  between 
the  tibia  and  fibula  to  the  back  and  lower 
part  of  the  os  femoris,  and  then  are  joined 
by  the  posterior  tibial  vein,  and  all  tlnree 
unite  to  form  the  femoral. 

The  posterior  tibial  vein  is  a  continua- 
tion of  the  small  metatarsal  vein,  and  cor- 
responds in  size  to  the  small  metacarpal. 
It  runs  in  company  with  the  posterior  tib- 
ial artery,  receiving  various  muscular 
branches  in  its  course,  also  the  medullary 
vein  of  the  tibia. 

The  femoral  vein  results  from  the  two 
last-named  vessels  ;  runs  behind  the  femoral 
artery,  and  ends  in  the  external  iliac  vein. 
It  receives  muscular  veins,  as  well  as  veins 
from  the  stifle  joint,  and  the  medullary  vein 
of  the  OS  femoris  ;  also,  about  two-thirds  of 
its  length  upwards,  it  is  joined  by  the  saph- 
ena  vein. 

The  vena  saphena  major  results  from  the 
large  metatarsal  vein  ;  at  the  hock  it  anas- 
tomoses with  the  anterior  tibial  vein;  it 
also  receives  cutaneous  and  muscular 
branches  in  its  course. 

The  vena  saphena  minor  springs  from  the 
small  metatarsal  vein ;  it  runs  up  the  back 
of  the  hock,  over  the  root  of  the  os  calcis, 
and  ultimately  reaches  the  femoral  vein. 

The  vena  porta  circulates  the  blood 
through  the  liver,  and  is  principally  formed 
by  the  union  of  the  splenic  and  mesenteric 
veins. 


THE   HORSE. 


169 


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ANATOMY    AND    PnYSIOLOGY    OP 


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EXPLANATION  OF   FIGURE  XYII. 


OSSEOUS  STRUCTURE. 

1.     Frontal  bones. 

3.  Occipital. 

4.  Temporal. 

8.  Superior  maxillaris. 

10.  Inferior  " 

11.  Cer-s-ical  vertebrae. 
14.  The  sacrum. 

16.  The  false  ribs. 

18.  The  sternum. 

19.  The  ileum. 

20.  The  ischium. 

21.  Pubis. 

22.  Femur. 

23.  Patella. 

24.  Tibia. 
e.  Fibula. 

25.  Os  calcis. 

26.  Tarsal  bones. 

27.  The  inferior  tarsal  bones. 

28.  Metatarsus  magnum. 

29.  Sessamoides. 

30.  Os  suffiaginis. 

31.  Os  corona. 

32.  Os  pedis. 

33.  Scapula. 

34.  Os  humeri. 

35.  Radius. 
y.  Os  uhiaris. 

36.  The  carpal  bones. 

37.  Metacarpus  magnum. 

38.  Sessamoids. 

39.  Os  corona. 

40.  Os  sufiraginis. 

41.  Os  pedis. 

d.  Dorsal  spines. 

MUSCULAR  STRUCTURE. 

THE  HEAD. 

a.  Orbicularis  palpebrarum, 

c.  Dilator  naris  lateraHs. 

e.  Orbicularis  oris, 
y.  Nasalis  longus, 
7i.  Buccinator. 

j.  Depressor  labii. 

Jc.  Masseter. 

10.  Region  of  the  parotid  gland. 

o.  Adducena  Tel  deprimene  aurem. 


EXPLANATION    OF   FIGURE    XVII.    CONTINUED. 
THE  NECK. 

6".  Ccn-ical  ligament.     Ligamentum  colli, 
c".   Trachclo  subscapularls,  scalenus. 
s.     Splenitis. 

r.  t.  Tendon  of  the  splenius  and  scalenus. 
u.     Levator  humeri. 

SUTEIUOn  V\B.T  OF  THE  SHOULDEIl  AND  BACK. 

r".   Latissimus  dorsi. 
u".  Trapezius. 

SIIOtTLDEH  AND  FORE  EXTREMITIES. 

g.  li".  Spinatus  muscles. 

Z".  m\  n\  Triceps  extensor  brachii. 

s".  a;".  Extensors  metacarj)i. 

p".  g".  Flexors  externus  ct  intemus. 

11.  u.  M.  «.  Flexors  perforans  et  perforatus. 

8.     The  pastern. 

fy.  ^•.  Hoofs. 

ABDOMINAL   REGION. 

c".   Abdominis  transversalis  externus. 
4.    Subcutaneous  thoracic  vein. 

POSTERIOR  EXTREMITIES. 

c'.    Erector  coccygis. 

ff.    Compressor  coccygis. 

t'.    Glutei. 

J'.  Triceps. 

k\   Biceps  abductor. 

V.    Abductor  tibialis  internus. 

r'.  r.  s\  Gastrocnemi. 

V.     Peroneus. 

q'.   Extensor  metatarsi  internus. 

u.    Insertion  of  the  gastrocnemius. 

V.     Flexor  perforans  et  perforatus. 

X.  y.  Fleshy  belly  of  the  extensors. 

8.    The  pastern. 

«,-.  ^-.  Hoofs. 


THE   HORSE. 


171 


THE  BRAIN  AND  ITS  APPEN- 
DAGES. 

The  cerebrum,  cerebellum,  and  medulla 
oblongata,  and  medulla  spinalis  are  invested 
with  three  membranes :  the  dura  mater,  pia 
mater,  and  tunica  arachnoides.  Of  these 
the  exterior  is  the  dura  mater  ;  which, 
though  called  a  membrane,  is  of  a  dense, 
tough,  and  inelastic  texture.  It  is  so  firmly 
adherent,  by  means  of  numerous  little 
prominences,  to  the  sutures  of  the  cranium, 
that  it  is  difficult  to  separate  them;  this 
membrane  is  to  the  internal  cranium  what 
the  pericranium  is  externally.  The  inner 
surface  of  the  dura  mater  is  lubricated  by 
a  fluid  furnished  by  its  own  blood-ves- 
sels. 

The  pia  mater  is  that  membrane  which 
closely  envelopes  the  substance  of  the 
brain,  and  dips  down  between  its  convolu- 
tions, and  adheres  to  its  surface  by  num- 
berless minute  blood-vessels.  It  differs  in 
its  appearance  and  texture  from  the  dura 
mater;  presenting  a  smooth  surface  exte- 
riorly, but  a  rough  and  villous  one  next  to 
the  brain,  and  being  composed  of  a  beauti- 
ful network  of  blood-vessels  united  together 
by  a  delicate  cellular  tissue. 

The  third  membrane  has  been  compared 
to  a  spider's  web,  in  allusion  to  which  the 
name  of  mcmbrana  arachnoides  has  been 
given  to  it. 

The  arteries  which  supply  the  brain  with 
blood  are  the  two  vertebrals,  besides  two 
other  branches  called  the  internal  carotids. 
Its  blood  is  returned  from  the  sinuses  of 
the  dura  mater  by  the  vertebral  and  jugular 
veins. 

It  is  on  the  supply  of  the  vertebral  ar- 
teries, however,  that  the  brain  mainly  de- 
pends for  its  supply,  for,  if  ligatures  are 
placed  on  these  arteries,  the  animal  dies; 
whereas,  both  the  carotids  may  be  tied 
without  occasioning  any  apparent  ill  effects. 
If  our  memory  serves  us.  Dr.  J.  C.  Warren, 
of  this  city,  has  performed  the  latter 
operation  on  the  human  subject  with  suc- 
cess. 

In  raising  the  bony  covering  of  the  brain, 


we  meet  with  two  processes,  called  the 
falx,  or  longitudinal  process,  and  the  ten- 
torium, or  transverse  process.  The  former 
resembles  the  blade  of  a  scythe,  hence  its 
name.  These  processes  are  formed  from 
duplicatures  of  the  dura  mater;  the  first 
descends  for  a  short  distance  between  the 
lobes  of  the  cerebrum.  It  takes  its  rise 
from  the  crista  galii,  and  terminates  on  the 
OS  occipitis. 

The  tentorium  is  extended  from  the  inner 
plate  of  the  os  occipitis  along  the  sides 
of  the  cranium  to  its  base,  whence  it  may 
be  traced  to  the  sphenoid  bone,  and  is 
lost  in  the  common  covering  of  the  dura 
mater.  It  is  composed  of  two  laminae :  one 
is  continuous  with  the  falx  :  the  other  forms 
that  portion  of  the  membrane  which  covers 
the  cerebellum.  The  tentorium  is  equally 
divided  by  the  falx  into  two  lateral  por- 
tions. 

The  sinuses.  —  The  superior,  or  longitu- 
dinal sinus,  runs  within  the  duplication  of 
the  falx,  along  its  superior  border. 

The  two  lateral  sinuses  are  formed  within 
the  duplicature  of  that  part  of  the  tento- 
rium which  is  attached  to  the  temporal  and 
occipital  bones  ;  one  extending  to  the  right, 
and  the  other  to  the  left.  They  receive 
veins  both  from  the  cerebrum  and  cerebel- 
lum. 

The  cavernous  sinuses,  so  named  from  the 
cavernous  appearance  of  their  interior ; 
they  receive  some  important  nervous  trunks 
in  their  passage  from  the  brain,  and  for 
lodging  the  terminations  of  the  internal 
carotid  arteries.  They  commonly  commu- 
nicate with  the  sub-occipital  sinus ;  these 
are  also  of  membranous  formation,  and  are 
found  upon  the  cuneiform  process  of  the  os 
occipitis,  running  longitudinally  to  the  fora- 
men magnum.  They  receive  veins  from 
the  cerebellum  and  posterior  parts  of  the 
cerebrum. 

Cerebrum.  —  The  largest  portion  of  the 
cerebral  mass,  and  that  which  presents  it- 
self to  our  view  in  raising  the  skull,  is  the 
cerebrum.  It  is  equally  divided  by  a  longi- 
tudinal fissure  along  its  middle,  into  which 
the  fabi  cerebri  descends ;  and  its  divisions. 


172 


ANATOMY  AND   PHYSIOLOGY   OP 


which  are  symmetrical,  both  internally  and 
externally,  arc  denominated  hemispheres. 

Cerebellum. —  The  cerebellum  is  at  once 
distinguished  from  the  cerebrum  by  its 
being  only  one-sixth  the  size  of  the  latter. 
Its  figure  is  irregular  :  it  has  two  oval  ends, 
and  its  lateral  dimensions  exceed  its  longi- 
tudinal. It  is  divided  into  three  oblong 
lobes  —  a  middle  and  two  lateral. 

Medulla  oblongata^  the  smallest  division 
of  the  cerebral  mass.  It  rests  on  the  cunei- 
form process  of  the  occipital  bone,  and  is 
continued  upward  and  backward  to  the 
foramen  magnum. 

The  upper  surface  of  the  medulla  oblong- 
ata forms,  with  the  tuber  annulare,  the 
floor  of  the  fom-th  ventricle. 

Pltuatary  gland,  a  red  body,  of  an  egg 
form,  seated  upon  the  sella  tursica,  within 
a  fold  of  the  dura  mater.  It  has  a  mem- 
branous capsule,  surrounded  by  cellular  ad- 
hesions, by  which  it  is  firmly  retained  in  its 
place. 

Medulla  spinalis.  —  The  spinal  marrow 
is  that  extended  portion  of  brain-like  sub- 
stance which  is  continued  from  the  poste- 
rior part  of  the  medulla  oblongata  through 
the  entire  length  of  the  spinal  canal.  It  is 
inclosed  in  the  same  membranes  that  en- 
velop the  brain ;  but,  in  addition  to  them, 
the  superior  ligament  of  the  spine  serves  as 
a  covering  and  defence  to  it  below.  To 
this,  and  to  the  periosteum  lining  the 
canal,  its  proper  theca  is  loosely  attached 
by  cellular,  adipose,  and  gelatinous  matter. 
Its  dura  mater  is  derived  from  that  which 
covers  the  brain :  in  beinsr  continued  through 
the  foramen  magnum,  the  membrane  is 
contracted  into  a  cylindrical  sheath  which 
loosely  encases  the  marrow,  and  is  generally 
described  under  the  denomination  of  theca 
vertebralis.  The  arachnoid  membrane  and 
pia  mater  have  the  same  relation  to  the 
marrow  that  the  same  membranes  have  to 
the  brain,  of  which  they  may  be  considered 
prolongations. 

ORIGIN    AND    DISTRIBUTION    OF    THE     NERVES. 

The  nerves,  being  symmetrical  in  number 
and  distribution  on  either  side  of  the  body. 


take  their  origin  in  pairs,  and  these  pairs 
are  numbered,  and  so  distinguished  from 
one  another,  according  to  the  order  in 
which  they  arise.  There  are  forty-six  pairs 
of  nerves  ;  ten,  coming  from  the  brain,  are 
distinguished  as  the  cerebral  nerves ;  thirty- 
sLx,  from  the  spinal  marrow,  denominated 
the  spinal  nerves. 

CEREBRAL    NERVES. 

First  pair,  or  olfactory  nerves,  arise  from 
the  corpora  strata,  along  the  posterior  bor- 
ders of  which  bodies  the  medullary  bands 
or  roots  of  them  may  be  traced  as  high  iip 
as  the  middle  lobes  of  the  cerebrum.  These 
are  the  largest  of  the  cerebral  nerves,  are 
bulbous  at  their  origin,  pulpy  in  texture,  and 
exhibit,  when  cut  into,  comparatively  to 
their  size,  large  cavities,  which  are  w^alled 
in  by  a  layer  of  medullary  matter,  enclosed 
wdthin  a  thinner  one  of  cortical  substance. 

Second  pair,  or  optic  nerves,  arise  from 
the  thalamia  nervorum.  They  leave  the 
cranium  through  the  optic  foramen,  and 
pass  to  enter  the  globe  of  the  eye,  within 
the  interior  of  which  it  expands,  and  forms 
the  retina.  In  its  whole  course,  it  is  en- 
closed within  a  sheath  prolonged  from  the 
dura  mater. 

Third  pair,  or  motores  oculorum,  take 
their  origin  by  several  filaments,  from  the 
inward  parts  of  the  crura  cerebri.  The 
trunk  of  the  nerve  first  runs  obliquely  out- 
ward, across  the  back  of  the  crus,  then 
turns  downward  and  enters  the  cavernous 
sinus,  on  through  the  foramen  lacerum-or- 
bitale.  In  entering  the  cavity,  the  nerve 
divides  into  two  branches.  The  smaller 
is  generally  received  by  the  levater  oculi. 
The  larger  branch  subdivides  into  several 
others ;  the  longest  of  these  runs  round  the 
eyeball,  and  penetrates  the  oblique  muscle. 
Two  or  three  others  run  to  the  abductor 
and  depressor  muscles. 

Fourth  pair  of  pathetic.  —  These  take  a 
filamentous  origin,  and  pass  the  border  of 
the  tentorium,  entering  the  cavernous  sinus, 
from  thence  to  the  orbit.  Its  destination 
is  the  superior  oblique  muscle  of  the  eye. 

Fifth  pair,  or  par  trigemini.  —  These  are 


THE   HORSE. 


173 


the  largest  nerves  of  the  brain.  They  take 
then-  origin  by  filaments  from  the  crura  cere- 
belli,  and  pierce  the  dm*a  mater.  Each 
nerve  appears  to  form  a  ganglion ;  from 
this  ganglion  we  say  that  three  nerves  de- 
part. One  is  called  the  ophthalmic;  the 
second,  the  anterior  maxillary ;  the  third  is 
the  posterior  maxillary  nerve.  The  oph- 
thalmic nerve  is  the  smallest  of  the  three 
divisions ;  as  it  emerges  from  the  orbit,  it 
divides  into  three  branches,  called  the 
lachrymal,  the  super-orbitar,  and  the  lateral 
nasal  branch. 

The  second  division.,  or  antei'ior  maxillary 
nerve,  leaves  the  cranium  through  the  hole 
called  foramen  rotundum,  of  the  sphenoid 
bone,  and  takes  its  passage  through  the 
inferior  orbital  canal,  whence  it  emerges, 
covered  by  the  levator  labii  superioris, 
upon  the  face :  here  it  splits  into  several 
large  branches,  denominated  the  facial 
nerves-  But  prior  to  its  entering  this  canal 
it  detaches  several  important  branches  to 
the  eyelid,  lachrymal  duct  ;  also  several 
long  filaments,  which  descend  on  the  tube- 
rosity of  the  anterior  maxilla,  penetrate  the 
bone,  and  furnish  twigs  to  the  antrum,  and 
the  two  [superior  molar  teeth.  The  largest 
branch  is  the  spheno-palatine,  or  lateral 
nasal  nerve,  to  wiiich  the  foramen  spheno- 
palatine gives  passage  into  the  nose, 
wherein  it  divides  into  two  sets  of  fila- 
ments. One  of  these  is  spread  over  the 
lateral  parietes  of  the  nasal  cavity ;  the 
other  ramifies  over  the  sinuses,  and  sends 
a  filament  to  the  lower  border  of  the  sep- 
tum. A  branch  also  goes  to  the  velum 
palati,  and  another  branch  accompanies  the 
palatine  blood-vessels,  and  ramifies  over  the 
soft  palate. 

The  facial  branches  of  this  division  ter- 
minate on  the  front  and  sides  of  the  face, 
and  receive  communicating  filaments  from 
the  anterior  facial  branch  of  the  portio 
dura,  and  with  them  form  a  plexus. 

The  third  division,  the  posterior  maxillary 
nerve,  gives  off  a  branch  which  runs  up  in 
front  of  the  parotid  gland,  and  joins  the 
portio  dm-a;  also  branches  called  the  buc- 
cal nerve,  pterygoideus,  and  gustatory.    The 


latter  descends  by  the  side  of  the  tongue, 
penetrates  that  organ  about  its  middle,  and 
vanishes  in  its  tip.  It  also  sends  ramifica- 
tions to  the  roots  of  the  incisive  teeth,  and 
to  the  under  lip. 

Sixth  pair,  or  abducentes,  arise  by  means 
of  filaments  from  the  medulla  oblongata ; 
this  nerve  gives  off  two  or  three  filaments 
to  the  retractor  oculi;  but  its  principal  des- 
tination is  to  the  abductor,  along  the  fasci- 
cula  of  which,  its  ramifications  are  equally 
distributed. 

Seventh  jjair,  or  auditory  nerves.  —  This 
pair  includes  two  separate  nerves  on  either 
side ;  one,  from  its  remarkable  softness,  is 
denominated  the  portio  mollis ;  the  other, 
in  contradistinction,  the  portio  dura.  The 
portio  mollis  enters  the  organs  of  hearing, 
and  is  distributed  to  the  labyrinth. 

The  portio  dura  arises  from  the  medulla 
oblongata,  and  passes  to  the  internal  part 
of  the  ear,  the  tympanum,  and  eustachian 
tube.  It  is  also  distributed  to  the  temples, 
eyelids,  nose,  lips,  cheek,  and  neck. 

Eighth  pair,  or  par  vagum.  —  At  its 
commencement  it  consists  of  two  separate 
portions  ;  the  first  called  the  glosso-pharyn- 
geal  nerve,  and  the  second  the  true  par  va- 
gum. They  arise  from  the  corpora  ohvaria, 
and  make  their  exit  through  the  base  of  the 
cranium.  The  glosso-pharyngeus  gives  off 
branches,  which  join  the  portio  dura,  to  the 
constrictors  of  the  pharynx,  and  form 
branches  which  ramify  in  the  base  of  the 
tongue. 

The  proper  par  vagum,  having  disunited 
from  the  glosso-pharyngeal  nerve,  proceeds 
downwards  to  join  the  carotid  artery,  and 
takes  its  course  along  the  neck  to  the  chest. 
Its  filaments  are  —  1.  To  the  cervical  gan- 
glion. 2.  The  pharyngeal  branch,  whose 
filaments  pass  to  the  esophagus  and  larynx. 
3.  Two  slender  branches  to  the  carotid  ar- 
tery, which  form  a  plexus.  4.  The  laryngeal 
branch. 

At  the  back  part  of  the  neck  the  par 
vagum  inclines  upwards,  and  is  found 
above  the  carotid  artery ;  it  then  passes 
between  the  two  first  ribs  into  the  chest. 
Having  entered  the  thoracic  cavity,  it  runs 


174 


ANATOMY   AND   PHYSIOLOGY   OF 


within  the  superior  mediastinum  ;  the  right 
nerve  adheres  to  the  trachea,  crosses  above 
the  root  of  the  right  lung,  alongside  of  the 
esophagus,  and  gains  the  under  side  of 
that  tube  before  it  leaves  the  chest.  On  iho 
left  side  the  nerve  accompanies  the  anterior 
aorta,  and  crosses  the  root  of  the  posterior 
aorta,  and  also  reaches  the  esophagus.  Its 
branches  within  the  chest  are  filaments  to 
the  tracheal  and  cardiac  plexuses ;  also,  a 
branch  called  the  recurrent  nerve ;  branches 
to  the  pulmonary  plexus,  and  also  two 
cords  that  branch  out  and  penetrate  the 
walls  of  the  auricles.  The  recurrent  nerve 
of  the  left  side  originates  from  the  par 
vagum,  by  the  side  of  the  anterior  aorta, 
and  coils  round  the  root  of  the  posterior 
aorta. 

The  recurrent  nerve,  so  denominated  from 
its  retrograde  course,  passes  upwardly  and 
outwardly,  and  is  found  between  the  caro- 
tid artery  and  the  trachea ;  having  reached 
the  top  of  the  latter,  it  spreads  into  fine  ter- 
minating branches,  several  of  which  run  to 
the  muscles  of  the  larynx  and  thyroid  carti- 
lage, and  end  in  ramifications  upon  the 
membrane  of  the  glottis.  Its  branches  are 
filaments  to  the  pulmonary  plexus,  cardiac 
plexus,  posterior  cervical  ganglion,  and 
branches  to  the  esophagus  and  trachea. 

The  par  vagum  runs  to  the  stomach. 
The  left  nerve  sends  filaments  to  the  heart, 
and  others  along  the  small  curvature,  which 
communicates  with  the  ramifications  of  the 
right  nerve ;  the  other  crosses  to  the  left 
side,  and  joins  the  great  semilunar  ganglion. 
The  right  nerve,  as  soon  as  it  reaches  the 
heart,  divides  into  numerous  branches, 
which  join  the  left,  and  spread  their  ramifi- 
cations upon  the  under  part  of  the  heart ; 
some  run  to  the  pylorus,  and  others  join  the 
hepatic  plexus. 

Accessory  nerves  to  the  eightli. —  These 
nerves  are  considered  as  accessory  to  the 
eighth,  in  consequence  of  their  being  found 
in  close  connection  in  issuing  from  the 
cranium ;  it  originates  in  the  vertebral  canal, 
by  the  union  of  several  filaments.  In  its 
course  into  the  cranium  it  receives  many 
other  fine  threads,  and  in  that  cavity  joins 


the  par  vagum.  Beneath  the  atlas,  the 
accessory  nerve  divides ;  the  front  division 
runs  downward,  and  penetrates  the  belly, 
transmitting  side  twigs  in  its  course.  The 
posterior  division  turns  round  the  transverse 
process  of  the  atlas  to  the  scapula,  near 
which  it  is  lost  in  muscular  substance. 
The  branches  of  the  accessory  pass  to  the 
par  vagum,  anterior  cervical  ganglion,  and 
communicate  with  the  sub-occipital  nerve. 

Ninth  pair,  or  Unguales,  arise  behind  the 
eighth  pair,  from  the  corpora  olivaria ;  it  is 
found  in  company  with  the  par  vagum,  near 
the  coronoid  process.  The  nerve  passes 
down  the  lower  jaw,  between  the  muscles* 
forming  the  root  of  the  tongue,  and  ends  in 
the  tip  of  the  latter.  It  sends  branches  to 
the  lingual  muscles  and  to  the  hyo-glossus 
longus. 

Tenth  pair,  or  sub-occipital  nerves. — They 
arise  from  the  medulla  oblongata,  and  be- 
ginning of  the  spinal  marrow;  they  pass 
out  through  a  hole  in  the  fore  part  of  the 
body  of  the  atlas.  It  then  branches  into  a 
superior  and  inferior  division.  The  superior 
is  distributed  to  the  extensor  muscles  of  the 
head  and  neck.  The  inferior  branch  goes 
to  the  trachea,  lymphatic  glands,  and  mus- 
cles of  the  neck. 

CERVICAL    NERVES. 

These  consist  of  seven  pairs,  originating 
from  the  cervical  portion  of  the  spinal  mar- 
row. Each  nerve,  as  soon  as  it  issues  from 
the  spinal  canal,  forms  two  ner\^ous  fila- 
ments, one  superior,  the  other  inferior. 

The  first  cervical  nerve  makes  its  exit  be- 
tween the  first  and  second  cervical  vertebra). 
It  sends  branches  to  difierent  muscles,  and 
communicates  wdth  the 

Second  cervical  nerve,  which  makes  its 
appearance  between  the  second  and  third 
vertebrae.  Its  superior  filament  sends 
branches  to  the  muscles  of  the  neck,  and 
levator  humeri,  communicates  -with  the  ac- 
cessory nerve,  and 

Third  cervical. — This  also  sends  branches 
and  twigs  to  the  difierent  muscles  of  the 
neck,  and  communicates  with  the  fourth. 

The  fourth,  fifth,  sixth,  and  seventh  pairs 


THE   nOESE. 


175 


pass  from  the  spine,  between  their  respec- 
tive vertebrae,  and  send  branches  to  the 
phrenic  nerve,  and  ramifications  to  the  mus- 
cles, sympathetic  nerve,  and  unite  with  the 
dorsal. 

THE    DIAPHRAGMATIC    OR    PHRENIC    NERVE. 

This  is  formed  by  branches  from  several 
of  the  cervical  nerves.  It  takes  its  course 
down  along  the  inferior  border  of  the  scale- 
nus muscle.  It  terminates  by  numerous 
ramifications  on  the  tendinous  parts  of  the 
diaplu'agm. 

DORSAL    NERVES. 

These  consist  of  eighteen  pairs.  They 
pass  from  the  vertebral  canal  in  the  same 
manner  as  the  cervical,  having  superior  and 
inferior  branches.  The  inferior  branches 
follow  the  course  of  the  intercostal  blood- 
vessels, and  are  called  intercostal  nerves. 
The  superior  branches  are  distributed  to 
the  back  and  loins. 

LUMBAR    NERVES, 

Consist  of  five  pairs  (corresponding  to 
the  number  of  the  lumbar  vertebrae). 

TJie  first  nerve  ends  in  ramifications  near 
the  stifle,  and  gives  off  branches  to  the  last 
dorsal  nerve,  to  the  sympathetic,  and  to  the 
second  lumbar  nerve. 

The  second  7ierve  has  communication 
with  the  first  nerve,  and  sympathetic ;  also 
the  crural.  It  sends  one  division  to  the  fore 
part  of  the  haunch,  where  it  becomes  sub- 
cutaneous, and  ramifies  over  the  stifle.  The 
other  division  crosses  the  ilio-lumbar  artery, 
just  below  its  origin,  and  takes  nearly  a 
similar  course  to  the  inward  part  of  the 
haunch,  and  then  ramifies  upon  the  skin ;  in 
its  way  it  detaches  a  considerable  branch, 
called  the  spermaticus  externus,  which  passes 
through  the  abdominal  ring,  and  sends 
twigs,  in  the  male,  to  the  scrotum  and  tes- 
ticle ;  in  the  female,  filaments  go  from  it  to 
the  uterus,  udder,  and  external  labia. 

The  third  nerve  contributes  to  form  the 
crural  and  obturator.  It  sends  small 
branches  to  the  sympathetic,  psoas,  and 
obturator  nerves. 


The  fourth  nerve  sends  a  branch  to  the 
sympathetic,  contributes  to  the  production 
of  the  crural ;  and  also  sends  a  branch  to 
the  obturator. 

The  fifth  nerve  communicates  with  the 
sympathetic,  crural,  and  sciatic  plexus. 

SACRAL    NERVES, 

Consist  of  five  pairs;  a  superior  and  ir- 
ferior  fascicula.     The  superior  make  thej 
exit  through  holes  upon  the  upper  part  o 
the  sacrum,  and  are  there  buried  under  a 
thick  mass  of  muscle,  and  become  cutane- 
ous upon  the  outer  part  of  the  haunch. 

The  inferior  fascicula.  —  The  first  nerve 
largely  contributes  to  the  origin  of  the 
sciatic  plexus,  and  sends  a  branch  to  the 
gluteal  nerve ;  also  to  the  sympathetic  and 
second  lumbar  nerves.  The  second  nerve 
communicates  with  the  third  and  sympa- 
thetic, and  sends  branches  to  the  surround- 
ing muscles  and  sciatic  plexus.  The  third 
and  fourth  have  similar  connections.  The 
fifth  passes  into  the  coccygeal  muscles. 

COCCYGEAL     NERVES. 

These  issue  from  the  spine,  in  the  same 
manner  as  the  last  described.  They  com- 
municate with  one  another,  are  distributed 
to  muscles  in  the  vicinity,  and  end  in  fila- 
mentous ramifications  at  the  end  of  the  tail. 

NERVES  OF  THE  FORE  EXTREMITY. 

The  fore  extremity  receives  its  nerves 
from  the  axillary  or  humeral  plexus,  and 
this  plexus  is  formed  by  the  union  of  por- 
tions of  the  sixth  and  seventh  cervical 
nerves,  'and  a  division  of  the  first  dorsal 
nerve. 

The  external  thoracic  nerves,  six  or  seven 
in  number,  arise  fi'om  the  humeral  plexus, 
and  are  distributed  to  the  pectoral,  triceps, 
and  other  muscles ;  they  finally  ramify  into 
the  skin. 

The  scapular  nerves  are  called  anterior, 
posterior,  and  sub-scapular.  The  former 
sends  its  ultimate  filaments  to  the  triceps. 

The  posterior  scapular  nerve  sends 
branches  to  the  sub-scapularis,  triceps,  teres 


176 


ANATOMY   AND   PHrSIOLOGY   OF 


minor,  and  shoulder  joint,  and  ends  in  the 
insertion  of  the  levator  humeri. 

The  subscapular  nerves  run  upward  be- 
tween the  shoulder  and  chest,  and  enter  the 
subscapularis. 

The  spiral  or  external  cutaneous  nerve  is 
furnished  by  the  axillary  plexus ;  arises  be- 
hind the  humeral  artery,  and  passes  between 
the  OS  humeri  and  the  head  of  the  triceps, 
through  the  extensors,  to  the  external  flexors 
of  the  canon.  It  gives  off  several  branches 
to  the  triceps,  ramifies  on  the  fore  and  out- 
ward part  of  the  knee,  and  sends  branches 
to  the  heads  of  the  extensor  muscles. 

The  radial  nerve  descends  with  the 
humeral  artery  to  the  inward  side  of  the 
elbow  joint,  and  runs  along  the  back  part 
of  the  radius  to  the  knee ;  passing  under 
the  annular  ligament,  it  descends  to  the  leg, 
and  takes  the  name  of  the  internal  metacar- 
pal ners'e.  It  gives  off  numerous  tvv^igs  to 
the  muscles,  and  finally  becomes  subcutane- 
ous. 

The  ulnar  nerve  originates  from  the 
humeral  plexus.  It  passes  down  the  radius, 
under  the  annular  ligament,  to  the  tendo 
perforans,  and  there  becomes  the  external 
metacarpal  nerve.  It  gives  off  internal 
cutaneous  and  subcutaneous  branches,  rami- 
fies into  cellular  substance,  penetrates  the 
heads  of  the  flexors,  and  finally  disperses 
its  ramifications  in  front  of  the  leg. 

The  metacarpal  nerves  continue  down 
the  leg,  over  the  fetlock  joint,  where  they 
become  the  plantar  nerves  ;  these  pm'sue 
their  course  behind  their  corresponding 
blood-vessels  to  the  back  part  of  the  foot, 
which  they  penetrate  to  the  inner  ■  side  of 
the  lateral  cartilages. 

The  plantar  nerve  detaches  a  branch  from 
the  fetlock  to  the  lateral  cartilage ;  another 
passes  to  the  fatty  frog.  The  final  branch 
enters  a  hole  in  the  back  and  lower  part  of 
the  coffin  bone,  in  company  with  the  plan- 
tar artery,  and  there  divides  and  distributes 
its  ultimate  branches  around  the  edges  of 
the  sole. 

NERVES    OF    THE    HIND    EXTREMITY. 

The  crural  nerve  is  derived  partly  from 


the  second,  third,  fourth,  and  fifth  lumbar 
nerves.  It  makes  its  appearance  under  the 
transverse  process  of  the  loins,  and  proceeds 
in  a  line  with  the  external  iliac  artery.  It 
gives  off  filaments  to  the  psoas  magnus, 
iliacus,  rectus,  and  vastus  internus  muscles. 
It  also  gives  off  cutaneous  filaments ;  one 
runs  to  the  stifle,  and  ends  in  ramifications 
upon  the  fore  part  of  the  thigh.  The  other 
continues  down  the  leg,  and  can  be  traced 
as  low  as  the  fetlock.  » 

The  obturator  nerve,  contributed  to  by 
third  and  fourth  lumbar  nerves,  sweeps 
round  the  brim  of  the  pelvis,  and  detaches 
twigs  to  the  obturator  muscles.  Its  ultimate 
filaments  are  expended  on  the  triceps  and 
gracilis. 

The  gluteal  nerve,  after  leaving  the  cavity 
of  the  pelvis,  accompanies  the  gluteal  artery, 
and  passes  into  the  substance  of  the  gluteal 
muscles. 

The  sciatic  nerve  derives  its  origin  from 
the  sacral  and  last  of  the  lumbar  nerves ; 
after  leaving  the  cavity  of  the  pelvis,  passes 
between  the  Mp  joint  and  the  tuberosity  of 
the  ischium,  and  plunges  into  the  substance 
of  the  haunch.  Here  it  divides  into  branches 
called  the  popliteal  nerves.  At  the  hock  its 
principal  branch  separates  into  the  external 
and  internal  metatarsal  nerves ;  the  former 
runs  over  the  flexor  pedis  to  the  os  calcis. 
Their  subsequent  com*se  and  ultimate  dis- 
tribution are  the  same  as  those  of  the  plan- 
tar nerves  of  the  fore  extremity.  The  second 
popliteal  nerve  passes  between  the  bellies 
of  the  gastrocnemii,  above  the  first,  detach- 
ing twigs  to  them  in  its  passage,  and  then 
spreads  into  many  branches,  which  pene- 
trate the  heads  of  the  flexor  muscles  of  the 
foot,  and  send  filaments  into  the  stifle  joint. 

SYMPATHETIC    NERVE. 

This  nerve  derives  its  name  from  the  uni- 
versal influence  which  it  has  on  the  nervous 
system.  It  communicates  with  the  head, 
neck,  chest,  pelvis,  and  abdomen,  by  its  fre- 
quent intercourse  and  connection  with  their 
respective  nerves.  It  is  supposed  by  some 
writers  to  be  a  nervous  system  of  itself. 
It  has,  at  different  distances,  a  great  uumber 


THE   HORSE. 


177 


of  gangliform  tubercles,  from  which  ramifi- 
cations proceed  forward,  as  well  as  filaments 
backward,  to  the  ganglia  of  the  nerves  of 
the  medulla  spinalis.  It  is  considered  gen- 
erally as  beginning  from  a  branch  of  the 
fifth  and  sixth  pair,  given  off"  at  the  base  of 
the  cranium.  The  ganglionic  structures 
and  the  different  plexuses  are  named  from 
their  form,  location,  and  distribution  ;  hence 
we  have  the  cervical  ganglion,  semilunar, 
sacral,  etc.  From  the  semilunar  ganglion 
nervous  filaments  shoot  in  various  direc- 
tions, which,  from  their  being  compared  to 
the  rays  of  the  sun,  are  denominated  the 
solar  plexus.  From  the  divergent  filaments 
of  the  latter,  the  several  smaller  plexuses 
of  the  abdomen  may  be  said  to  derive 
their  formation,  taking  names  according  to 
the  viscera  they  are  particularly  designed  to 
furnish  with  nerves ;  hence  we  have  the 
splenic  plexus,  that  sends  filaments  to  the 


spleen,  the  hepatic  plexus,  mesenteric,  aortic, 
hypogastric,  and  renal  plexuses.  The  sym- 
pathetic nerve  in  the  abdomen  travels  over 
the  sides  of  the  bodies  of  the  lumbar  verte- 
brae, below  the  articulations  of  the  ribs,  and 
pursues  its  course  into  the  pelvis.  Here, 
also,  it  forms  ganglia,  which  correspond  in 
number  to  those  of  the  lumbar  nerves :  and 
from  every  ganglion  come  off  two  filaments : 
one  which  runs  to  the  corresponding  lumbar 
nerve ;  the  other  crosses  the  aorta,  and,  by 
joining  the  aortic  plexus,  communicates 
with  nerves  coming  from  the  sympathetic 
of  the  other  side. 

From  the  loins,  the  sympathetic  descends 
into  the  pelvis,  and  takes  its  course  along 
the  side  of  the  sacrum,  and  forms  five  gan- 
glia, corresponding  to  the  sacral  nerves ;  it 
finally  terminates  by  forming  a  union  with 
its  fellow. 


EXAMINATIONS  ON  NEUROLOGY. 


Examinations  on  Neurology,  which  will  include  the 
names  of  parts  not  alluded  to  in  the  preceding 
summary  of  the  nervous  system. 


Q.  What  are  nerves  ?  —  A.  Long,  firm,  and  white 
chords,  which  ramify  after  the  manner  of  blood-vessels, 
and  are  distributed  to  all  parts  of  the  horse's  body. 

Q.  Where  do  they  arise?  —  A.  From  the  brain, 
medulla  oblongata,  and  medulla  spinalis. 

Q.  AVhat  communications  have  the  chfFerent  nerves 
with  each  other?  —  A.  They  anastomose :  forming 
sometimes  a  plexus;  at  others,  a  knot  or  ganglion, 
from  which  other  branches  arise. 

Q.  What  is  the  structure  of  nerves? — A.  They 
consist  of  fasciculi,  or  bundles,  of  distinct  longitudinal 
fibres,  closely  connected  together  by  cellular  substance. 

Q.  What  are  the  coverings  of  nerves  ?  —  A.  Contm- 
uations  of  those  which  envelop  the  brain  and  spinal 
marrow,  termed  neurilema. 

Q.  What  is  the  structm-e  of  ganglions  ?  —  A.  They 
are  formed  by  a  close  intermixtiu-e  of  filaments. 

BRAIN  AND  ITS  MEMBRANES. 

Q.  Where  is  the  brain  situated?  —  A.  It  occupies 
the  cranial  cavity. 

Q.  How  is  the  brain  diA-ided  ?  —  A.  Into  cerebrum, 
cerebellum,  and  medulla  oblongata. 

Q.  By  what  membranes  is  the  brain  enveloped  ?  — 
A.  By  three  membranes,  or  meninges:    1st,  The  dura 
mater ;  2d,  Pia  mater ;  3d,  tunica  arachnoides. 
23 


DURA  MATER. 

Q.  What  is  the  situation  of  the  dura  mater  ?  —  A. 
It  is  the  external  covering  of  the  braui. 

Q.  How  does  it  differ  from  the  other  coverings  of  the 
brain  ?  —  A.  It  is  more  dense,  tough,  and  inelastic. 

Q.  How  is  it  retained  within  the  cranium  ?  —  A.  It 
is  fii'mly  adherent  to  the  interior  of  the  cranium,  more 
particularly  to  the  depressions  between  the  teeth  of  the 
cranial  sutures. 

Q.  How  does  the  internal  differ  from  the  external 
surface  ?  —  A.  It  has  a  smooth,  poUshed,  and  lubricated 
surface. 

Q.  Is  the  dura  mater  suppHed  with  nerves?  —  A. 
Being  composed  of  tendinous  fibre,  it  is  supposed  to  be 
destitute  of  nerves. 

Q.  How  are  the  processes  of  the  dura  mater- 
formed  ?  —  A.  By  dupHcatiu*es. 

Q.  What  are  the  use  of  the  processes  ?  —  A.  They 
steady  and  protect  the  various  divisions  of  the  brain. 

Q.  By  what  names  are  the  processes  known  ?  —  A. 
The  longitudinal  process  is  called  falx  cerebri,  and  the 
transverse  ditto  is  called  tentorium. 

Q.  What  is  the  situation  of  the  falx  cerebri  ?  —  A. 
It  forms  a  partition  under  the  anterior  and  superior 
parts  of  the  cranial  cavity  extending  from  the  crista 
galU  to  the  occiput,  and  ends  in  continuity  with  the 
tentorium. 

Q.  What  is  the  situation  of  the  tentorium  cerebelli  ? 
—  A.  It  is  extended,  after  the  manner  of  an  arch,  from 
the  cerebral  plate  of  the  occipitis  along  the  sides  of 


178 


ANATOMY   AND   PHYSIOLOGY   OP 


the  cranium  to  its  base ;  whence,  greatly  diminislied  in 
breadth  it  continues  onward  to  the  os  sphcnoidos. 

SINUSES  OF  THE  DURA  MATER. 

Q.  What  are  the  names  of  the  principal  sinuses  of 
the  dura  mater?  —  A.  The  superior  or  longitudinal 
sinus;  two  lateral, cavernous,  and  sub-occii^ital  sinuses, 

riA    MATER. 

Q.  "What  is  the  situation  of  the  pia  mater  ?  —  A.  It 
surrounds  and  closely  invests  the  convolutions  of  the 
brain,  and  passes  into  the  ventricles,  furnishing  them 
■with  an  internal  membrane. 

Q.  AVhat  is  the  structure  of  the  pia  mater?  —  A.  It 
presents  a  smooth  exterior  surface ;  next  the  brain  it 
is  rough  and  villous,  and  is  composed  of  a  network  of 
blood-vessels,  which  are  united  together  by  a  delicate 
cellular  tissue.  Being  highly  vascular,  it  is  supposed 
that  the  blood-vessels  of  the  brain  ramify  in  it  before 
entering  the  latter. 

ARACUXOID  MEMBRAXE. 

Q.  "Where  is  the  tunica  arachnoidea  situated  ?  —  A. 
It  is  a  delicate  and  transparent  membrane,  spread 
imiformly  over  the  sm'face  of  the  brain. 

CEREBRUM. 

Q.  Where  is  the  cerebi*um  situated  ?  —  A.  It  occu- 
pies the  superior  part  of  the  cranium. 

Q.  AVhat  is  its  form,  and  how  is  it  dinded  ?  —  A.  It 
is  oval,  convex  above  and  concave  below,  and  is  diA-ided 
by  a  longitudinal  fissure  along  its  middle,  into  which 
the  falx  cerebri  descends.  Its  di\isions  are  denom- 
inated hemispheres. 

Q.  What  is  the  appearance  of  the  sm-face  of  the 
cerebrum?  —  A.  It  is  covered  with  eminences  called 
convolutions. 

Q.  Of  what  is  the  substance  of  the  brain  supposed  to 
consist  ?  —  A.  Of  two  kinds  of  matter ;  the  external  is 
called  cortical  or  cineritious,  and  the  internal  is  termed 
medullary. 

Q.  What  is  the  color  of  the  cortical?  —  A.  Red- 
dish-ash. 

Q.  What  is  the  color  of  the  medullary  portion  ?  — 
A.  Of  a  milk-white  hue. 

CORPUS   CALLOSXM. 

Q.  What  is  the  situation  of  the  corpus  callosum  ?  — 
A.  It  is  an  oblong  Mhite  body,  located  at  the  bottom  of 
the  fissure  which  divides  the  two  hemispheres  of  the 
brain. 

Q.  What  docs  the  corpus  callosum  join  on  each 
side?  —  A.  Its  edges  blend  vdth.  the  medullary  sub- 
stance of  the  two  hemispheres  of  the  cerebrum. 

Q.  What  name  is  given  to  the  medullary  substance 
of  both  hemispheres,  together  with  the  corpus  callosum, 
when  the  usual  anatomical  section  is  made?  —  A.  By 
cutting  off"  the  hemispheres  of  the  cerebrum  nearly 
even  with  the  corpus  callosum,  there  is  seen  a  large 


oval  mass  of  medullary  substance,  called  the  centrum 
ovale. 

LATERAL   VENTRICLES. 

Q.  What  are  the  lateral  ventricles  ?  —  A.  Two  cavi- 
ties situated  beneath  the  corpus  callosum  and  medullary 
arches  of  the  cerebrum. 

Q.  What  divides  the  lateral  ventricles  from  each 
other?  —  A.  The  septum  lucldum. 

Q.  Name  the  parts  which  are  generally  considered  as 
the  contents  of  the  lateral  ventricles.  —  A.  They  are 
the  corpora  striata,  the  hippocampi,  plexus  choroides, 
fornix,  and  the  thalami  nervorum  opticorum. 

Q.  What  is  the  situation  and  form  of  the  corpora 
striata? — A.  They  are  found  on  the  lower  and  back 
parts  of  the  ventricles,  projecting  into  the  centre  of 
the  canities,  where  they  expand  as  they  approach  the 
septum ;  grow  narroAver  and  recede  from  each  other 
above ;  below,  they  extend  to  the  anterior  cornua. 

HIPPOCAMPI. 

Q.  What  is  the  situation  of  the  liippocampi  ?  —  A. 
They  occupy  the  superior  spaces  of  the  ventricles  in 
contact  with  the  septum. 

Q.  From  whence  do  they  originate  ?  —  A.  From  the 
centres  of  the  hemispheres. 

Q.  What  is  their  structure?  —  A.  They  consist  of 
alternate  laminae  of  medullary  and  cortical  matter. 

PLEXUS   CHOROIDES. 

Q.  What  is  the  situation  of  the  plexus  choroides  ?  — 
A.  They  are  situated  in  the  channel  between  the 
corpus  striatum  and  hippocampus. 

Q.  Describe  the  appearance  of  the  same  ?  —  A.  It  is 
a  soft  vascular  substance,  consisting  of  a  plexus  of 
minute  blood-vessels;  it  makes  its  appearance  from 
behind  the  fornix,  and  ends  abruptly  in  a  round  bulbous 
mass. 

FORNIX. 

Q.  Describe  the  fornix  audits  situation?  —  A.  The 
fornix  is  that  pai't  wliich  receives  the  posterior  border 
of  the  septum  lucidum.  It  is  extended  after  the 
manner  of  an  arch,  between  the  corpora  stratia  below 
and  the  heads  of  the  hi])pocampi  above,  where  it  forms 
a  junction  Avith  the  corpus  callosum. 

Q.  Describe  the  processes  or  crura  of  the  fornix  ?  — 
A.  The  two  inferior  crura  spring  from  the  corpus 
albicantium,  at  the  base  of  the  brain,  and  finally  unite; 
thus  united,  they  appear  within  the  ventricles  and  con- 
stitute the  body  of  the  fornix.  The  superior  crura 
proceed  from  the  upper  end  of  the  fornix,  and  descend 
into  the  superior  cornua  of  the  lateral  ventricles,  and 
end  in  sharp,  pointed  extremities. 

TILAXAMLV. 

Q.  What  is  the  situation  of  the  thalamia  nervorum 
opticorum  ?  —  A.  They  form  the  upper  and  back  parts 
of  the  lateral  ventricles. 

Q.  Describe  the  thalamia.  —  A.    They  have  a  white 


THE   HORSE. 


179 


'  appearance,  conoid  in  form,  narrow  and  approximated 
inferiorly ;  broad  superiorly ;  they  finally  contract  into 
medullary  bands,  the  tractus  optici,  wliich  turn  round 
the  crura  cerebri  to  the  base  of  the  brain. 

Q.  How  are  the  thalami  distinguished  from  the 
corpora  striata  ?  —  A.  They  are  more  dense  and  firmer 
in  composition. 

TAENIA. 

Q.  What  is  the  situation  of  the  taenia  ?  —  A.  They 
are  located  in  the  groove  between  the  thalamus  and 
corpus  striatum,  partly  covered  by  the  plexus  choroides. 

COMMISURES. 

Q.  Name  the  commisures  of  the  brain.  —  A.  1st, 
commissm'a  mollis ;  2d,  commism'a  inferior  cerebri  ; 
3d,  commism-a  superior  cerebri. 

Q.  How  is  the  commisura  mollis  formed  ?  —  A.  By 
contiguous  parts  of  the  thalami,  which  are  united  by 
cortical  matter. 

Q.  How  is  the  commisura  inferior  cerebri  formed  ? 
—  By  a  connection  between  the  hemispheres  of  the 
brain. 

Q.  Where  is  the  superior  commissure  located  ?  —  A. 
Above  the  commissura  mollis ;  it  has  the  appearance  of 
a  short  medullary  chord. 

FORAMEN. 
Q.  What  is  the  foramen? — A.    It  is  a  triangular 
depression  under  the  arch  of  the  fornix,  into  which  the 
lateral  ventricles  open. 

"STEXTRICLES. 

{^Remarks.  —  Having  put  the  usual  question  regarding 
the  lateral  ventricles,  which  may  be  numbered  1  and 
2,  we  now  come  to  the  third  ventricle,  which  is  not  so 
well  marked  as  in  the  human  subject.] 

THIRD  A'ENTRICLE. 

Q.  How  is  the  third  ventricle  formed?  —  A.  By  a 
mere  fissm-e  existing  between  the  thalami. 

[Remarks.  —  The  fourth  ventricle,  being  located  in 
the  cerebellum,  will  be  considered  under  this  head.] 

INFUNDIBULUM. 

Q.  Where  is  the  infundibulum  located  ?  —  A.  At  the 
inferior  part  of  the  thii'd  ventricle. 

PINEAL  GLAND. 

Q.  Where  is  the  jjineal  gland  located  ?  —  A.  Be- 
tween the  summits  of  the  thalami,  over  the  third 
ventricle,  and  above  and  before  the  superior  com- 
missure. 

Q.  Describe  the  jjineal  gland.  —  A.  It  is  a  small 
conoid  body,  of  grayish  color,  marked  by  a  slight 
depression  along  its  centre. 

Q.  What  are  its  attachments?  —  A.  It  is  attached 
•  by  means  of  the  pia  mater  to  the  thalami  and  tuber- 
cula  quadragemina, 

Q.  What  is  the  internal  structure  of  the  pineal 
gland  ?  —  A.  It  consists  of  cortical  and  granular 
matter. 


NATES  AND  TESTES. 

Q.  Where  are  the  nates  and  testes  situated  ?  —  A. 
Above  the  third  ventricle,  behind  the  pineal  gland,  and 
immediately  over  and  within  the  third  and  fourth  ven- 
tricles. 

Q.  How  do  the  nates  differ  from  the  testes? — A. 
The  former  are  larger  than  the  latter,  and  are  separated 
by  a  groove  from  the  testes,  and  by  a  deep  perpendicular 
fissure  from  each  other. 

Q.  What  is  their  form  ?  —  A.  Semi-oval. 

Q.  What  is  their  composition?  —  A.  They  are  com- 
posed of  cineritous  and  medullary  matter. 

CEREBELLUM. 

Q.  What  is  the  situation  of  the  cerebellum  ?  —  A.Jxi 
the  inferior  and  posterior  parts  of  the  cranium. 

Q.  How  does  the  cerebellum  compare  in  size  with, 
the  cerebrum?  —  A.  The  former  is  only  about  one- 
sixth  the  volume  of  the  latter. 

Q.  Describe  the  appearance  of  the  cerebellum  ?  — -A. 
Its  surface  is  lobular  and  convoluted;  its  form  is 
irregular,  having  two  oval  ends  placed  transversely, 
united  in  the  centre  by  a  broad  vermiform  belt;  its 
lateral  dimensions  exceed  its  longitudinal. 

Q.  How  is  the  cerebellum  divided  ?  —  A.  Into  three 
lobes,  a  central  and  two  lateral. 

Q.  How  does  the  composition  of  the  cerebellum 
differ  from  that  of  the  cerebrum  ?  —  A.  In  the  former 
the  cortical  substance  exceeds  the  medullary,  and, 
instead  of  forming  the  bulk  of  the  outer  parts,  as  is 
the  case  in  the  cerebrum,  it  pervades  the  inner. 

FOURTH  VENTRICLE. 

Q.  What  is  the  situation  of  the  fom'th  ventricle  ?  — 
A.  It  is  situated  between  the  cerebellum,  tuber  annu- 
lare, and  medulla  oblongata. 

Q.  Where  is  the  choroid  plexus  of  the  cerebellum 
situated?  —  A.  Within  and  across  the  posterior  part 
of  the  fourth  ventricle,  between  the  cerebellum  and 
medulla  oblongata. 

Q.  How  is  the  choroid  plexus  of  the  cerebellum  dis- 
tributed ?  —  A.  It  is  distributed  into  three  di\-isions : 
one  lies  in  the  middle  of  the  calamus ;  the  two  latter 
are  found  witliin  fissures  in  the  cerebellum,  occupjing 
the  spaces  between  it  and  the  tuber  annulare. 

BASE   OF  THE  BRAIN. 

Q.  How  is  the  base  or  posterior  part  of  the  cerebrum 
divided?  —  A.  It  is  di\-ided  into  six  lobes. 

Q.  Describe  their  dimions.  —  A.  There  are  tAvo 
anterior  or  inferior,  resting  upon  the  wings  of  the 
ethmoid  bone ;  two  middle,  upon  those  of  the  sphenoid; 
and  two  superior  or  posterior,  lodged  in  the  fossa  of  the 
squamous  portions  of  the  temporal  bones. 

Q.  AVhat  name  is  given  to  two  broad,  smooth  promi- 
nences which  a^^pear  over  the  middle  lobes  at  the  base 
of  the  brain  ?  —  A.  These  are  the  corpora  striata. 

Q.  What  nerves  originate  from  this  vicinity?  —  A. 
The  olfactorv  nen'es. 


laa 


ANATOMY   AND   PHYSIOLOGY   OF   THE   HORSE. 


Q.  ■V\niat  lobes  rest  on  the  wings  of  the  sjjhenoid 
bone?  —  A.  The  criu'a  cerebri. 

Q.  From  whence  do  they  arise?  —  A.  From  the  in- 
ferior and  middle  lobes  of  the  cerebrum,  and  arc  con- 
tinued into  an  ovoid  protuberance  above  them,  named 
tuber  annulare. 

Q.  "What  is  observable  between  the  crura  cerebri  ? 
—  A.  A  small  hcmisi)herical  medullary  eminence, 
called  corpus  albicantium. 

Q.  Where  are  the  tractus  optici  situated  ?  —  A.  They 
wind  obliquely  doAvnward  around  the  crura. 

Q.  Where  do  they  proceed  from  ?  —  A.  From  the 
terminations  of  the  thalami. 


Q.  What  is  the  situation  of  the  crura  cerebelli  ?  —  A- 
They  are  located  higher  up  and  in  a  more  outward 
direction  than  the  crura  cerebri. 

Q.  Describe  the  crura  cerebelU.  —  A.  They  are  two 
1  cyUndroid,  medullary  chords,  wliich  join  the  lateral 
j  lobes  of  the  cerebellum  to  the  tuber  annulare. 

Q.  What  does  the  tuber  annulare  rest  upon  ?  —  A. 
On  the  cuneiform  process  of  the  posterior  occipital 
bone. 

Q.  Where  are  the  forumina)  ca;ca  situated  ?  —  A. 
Above  and  below  the  tuber. 

Q.  What  is  their  appearance  ?  —  A.  They  are 
described  as  little,  round  depressions,  or  blind  holes. 


EXPLANATION   OF   FIGURE   XVITi 

[from  Blaine's  "  outlines."] 


THE   HEAD. 

A.  The  skull,  face,  and  upper  jaw,  in  one  piece. 

B.  Lower  jaw. 
a.    Incisor  teeth. 
6.    Tushes. 

c.  jVIolares,  or  grinders. 

d.  Peak  formed  by  the  extremities  of  the  nasal  bones. 

e.  Zygomatic  spine,  to  the  bottom  of  which  the  masseter  takes  its  origin. 
/.  Orlnt. 

g.    Ca-\ity  above  the  orbital  arch. 

h.   Pole. 

i.    Zygomatic  arch. 

j,j.  Styloid  processes  for  the  attachment  of  the  muscles. 

k.    Joint  formed  by  the  upper  and  lower  jaws. 

I.     IMeatus  auditorius,  or  opening  to  the  internal  ear. 

THE  NECK. 

C.  C.  Marks  the  extent  of  the  cervical  vertebrae. 

D.  Dentata. 
m.  Atlas. 

n.    Wing  of  the  atlas. 

0,  Large  superior  spine  of  the  dentata. 
p.  Body  of  the  dentata. 

q.    Inferior  spine  of  the  dentata. 

s,  s,  s,  s,  s.  Superior  spines  of  the  five  remaining  cer-vical  vertebrae. 

r,  r,  r,  r,  r.  Oblique  processes  of  the  five  last  cer%ical  vertebrae. 

u,  u,  u,  u,  it.  Transverse  processes  of  the  same  bones. 

t,  t,  t,  t,  t.  Inferior  spines  of  the  five  last  cervical  vetebrae. 

THE  THORAX. 

V,  V.  Cariniform  process  of  the  sternum. 

w,  w,  w,  to,  w,  w,  w.  Costae  or  true  ribs. 

y>  y>  2/'  Z/'  2/»  2/>  2/'  y^  yi  y-  ^'^^  as  distinguished  from  the  costse. 

X,  X,  X,  X,  X,  X,  X,  X,  X.  Cartilages  by  means  of  which  the  ribs  are  attached  to  the  sternum. 

z,  z,  z,  z,  z,  z,  z.  Heads  of  the  ribs. 

1,  1,  1,  1,  1.  Superior  spines  of  the  first  five  dorsal  vertebra,  the  fifth  being  generally  the  longest  spine  in  the 

body. 

2,  2,  2,  2,  2,  2,  2,  2.  Superior  spines  from  the  sixth  to  the  thirteenth,  towards  which  they  slope  downward; 

the  thirteenth  is  generally  the  most  upright  spine  in  the  dorsal  region. 

3,  3,  3,  3,  3.  Last  five  of  the  superior  of  the  back  spines,  which  have  an  inclination  forward. 

THE  LOIXS,   OK  LUMBAR  REGIOX. 

4,  4,  4,  4,  4,  4.  Superior  spines  of  the  liunbar  region,  thicker  than  the  dorsal  spines,  and  having  a  decided  in- 

clination forward. 

5,  5,  5,  5.  Projecting  transverse  processes  of  the  loins, 

THE  SACRUM. 

6,  6,  6,  6,  6.  Superior  spines  of  the  sacrum  leaning  decidedly  backward,  thus  lea\'ing  a  large  space  between  the 

points  of  the  last  lumbar  and  the  first  sacral  spine,  at  which  place  occurs  the  great  hinge  of  the  back. 
8,  8,  8,  8.  Bodies  of  the  sacral  vertebrae. 


7,  7,  7,  7,  7,  7,  7,  7,  7.  Coccygeal  bones. 


THE    TAIL. 


THE  PEL\^S. 


E.   Ossa  innominata,  consisting  of  three  bones  upon  each  side. 

a.    Ilium. 

h.     Pubis. 

c.     Ischium  :  the  three  bones  unite  at  the  cavity  which  receives  the  head  of  the  thigh  bone. 

9,  9.  The  inferior  spines  of  the  ilium. 

10.  Superior  spine,  which  partly  covers  the  first  sacral  spine. 
«•,  c.  Ischiatic  spines. 


182 


ANATOMY  AND   PHYSIOLOGY  OF 


nal  glands,  which  are  lodged  upon  the 
superior  and  anterior  part  of  the  thigh. 

"  The  deep-seated  lymphatics  take  their 
rise  from  the  foot,  ascend  along  with  the 
plantar  veins,  continue  upward  among  the 
muscles,  in  company  with  the  deep-seated 
veins,  corresponding  in  their  principal  di- 
visions to  those  vessels,  and  proceed  to  the 
inguinal  glands. 

"All  the  lymphatics  of  the  posterior 
limbs  assemble  at  these  glands,  and  here 
form  a  plexus,  from  which  several  large 
branches  depart  and  traverse  the  iliac 
glands,  clinging  to  the  sides  of  the  iliac 
vessels,  and  discharge  their  contents  into 
the  pelvic  branch,  contributing  to  the  recep- 
taculum  chyli. 

"  2.  Lymphatics  of  the  Pelvis.  —  The 
vessels  coming  from  this  cavity  run  in 
part  to  the  inguinal  glands,  and  in  part 
to  the  internal  pelvic  glands.  The  su- 
perficial lymphatics  about  the  pubes  and 
the  outlet  of  the  pelvis  run  and  join  those 
of  the  extremities ;  those  of  the  perineum 
and  anus  enter  the  cavity,  and  are  accom- 
panied by  those  coming  from  the  croup  and 
tail,  both  proceeding  to  the  glands  within 
the  interior  of  the  pelvis.  AU  the  deep- 
seated  lymphatics  accompany  the  veins, 
make  for  the  pelvic  glands,  form  union  with 
the  others,  and  run  and  empty  themselves 
into  the  main  pelvic  branch,  wherein  their 
lymph  mixes  with  that  coming  from  the  in- 
guinal glands. 

"  The  lymphatics  of  the  urinary  and 
genital  organs,  included  in  the  pelvic  cavity, 
also  traverse  the  glands  lodged  therein,  and 
unite  with  those  of  the  parietes  of  the  pel- 
vis. Those  of  the  scrotum  enter  the  in- 
guinal glands,  as  also  do  those  belonging 
to  the  sheath  and  penis.  The  ramifications 
derived  from  the  testicle  and  spermatic 
cord  take  the  course  of  the  veins,  and  pene- 
trate one  or  two  of  the  lumbar  glands 
lodged  at  the  entrance  of  the  pelvis.  The 
lymphatics  of  the  mammae,  which  are  also 
divisible  into  superficial  and  deep-seated, 
run  to  the  inguinal  glands,  and  anastomose 
with  the  superficial  set  belonging  to  the  in- 
ferior parietes  of  the  abdomen  ;  but,  before 


they  reach  these  last  glands,  they  pervade 
those  of  the  mamma?. 

"  3.  Lymphatics  of  the  Parietes  of  the  Ab- 
domen. —  These  vessels,  in  general  but  little 
developed,  for  the  most  part  run  to  the  in- 
guinal glands.  The  superficial  set  of  the 
lower  parietes  accompany  the  cutaneous 
inguinal  vein,  anastomose  with  the  lympha- 
tics of  the  scrotum  and  mammae,  and  tra- 
verse the  glands  in  the  groin :  some  of  them 
direct  their  course  forward,  along  with  the 
cutaneous  external  thoracic  veins  of  the 
thorax,  unite  with  the  superficial  lymphatics 
of  that  part,  and  proceed  to  the  axillary 
glands.  The  deep-seated  vessels  of  the 
belly  run  in  company  with  the  epigastric 
vein,  and  go  to  the  inguinal  glands,  or  else 
they  accompany  the  pectoral  vein,  and  per- 
vade the  glands  in  front  of  the  thorax. 

"  The  superficial  or  subcutaneous  lym- 
phatics of  the  loins  join  either  those  of  the 
croup  or  those  of  the  flanks :  the  deep- 
seated,  which  spring  from  the  peritoneum, 
muscles,  or  spinal  canal,  perforate  one  of 
the  lumbar  glands,  and  pass  onward  to  ter- 
minate in  the  main  pelvic  branch. 

"  4.  Absorbents  of  the  Mesentery.  —  The 
mesenteric  branches,  ordinarily  two  or 
three  in  number,  the  most  considerable 
of  which  is  constantly  united  to  the  great 
mesenteric  artery,  receive  aU  the  vessels 
continued  from  the  mesenteric  glands,  as 
well  as  those  coming  from  the  mesentery 
and  intestines. 

"  The  mesenteric  absorbents,  extremely 
numerous,  are  sustained  between  the  layers 
of  the  mesentery,  where  they  form  a  vascu- 
lar network ;  many  of  them  issue  from  the 
exhalent  surface  of  the  mesentery  and  in- 
testinal tube ;  others  take  their  rise  from 
the  interior  of  the  intestines,  from  which 
they  imbibe  chyle.  All  these  vessels  con- 
verge towards  the  lymphatic  reserv'oir, 
clinging  in  their  passage  around  the  mesen- 
teric veins  ;  some,  however,  taking  a  solitary 
course  at  a  greater  or  less  distance  from  any 
blood-vessel.  Having  arrived  at  the  root  of 
the  mesentery,  they  pass  through  one  or 
two,  sometimes  three,  of  the  mesenteric 
glands,  and  afterwards  join  the  principal 


THE   HORSE. 


183 


lumbar  lymphatics.  The  absorbents  of  the 
colon  and  coecum  caput  coli  run  to  the 
glands  set  at  intervals  along  the  intestinal 
tube,  whence  they  proceed  to  the  recepta- 
culum  chyli. 

"  5.  LTjmphatics  of  the  Liver,  Stomach, 
Spleen,  and  Omentum.  —  The  hepatic  trunk 
comprises  the  lymphatics  issuing  from  the 
above  viscera.  This  branch  of  the  recepta- 
culum  chyli  not  uncommonly  consists  of 
two  divisions,  and  receives  in  addition  to  the 
above-mentioned  vessels  many  ramifications 
from  the  crura  of  the  diaphragm. 

"  The  lymphatics  of  the  pancreas,  like 
the  above,  also  run  with  the  divisions  of 
its  veins,  and  join  either  those  of  the  liver 
or  those  of  the  spleen  :  some  proceed  di- 
rectly to  the  common  hepatic  trunk. 

"  II.  RAMIFICATIONS  TERMINATING  IN  THE 
THORACIC  PORTION  OF  THE  MAIN  COMMON 
DUCT. 

''1.  Lymphatics  of  the  Parietes  of  the 
Thorax.  —  The  superficial  absorbents  of 
the  chest  take  their  rise  either  from  the  sur- 
face of  the  skin  or  else  from  the  subcuta- 
neous muscles ;  they  form  several  large 
branches  which  accompany  the  thoracic 
cutaneous  vein,  unite  with  the  superficial 
lymphatics  coming  from  the  anterior  parie- 
tes of  the  abdomen,  and  proceed  to  the 
axillary  glands. 

"  The  deep-seated  set  take  divers  direc- 
tions, and  pass  through  the  different  sets  of 
glands.  The  pectoral,  which  anastomose 
with  ramifications  from  the  abdomen,  fol- 
low the  pectoral  vein,  and  reach  one  or  two 
glands  at  the  entrance  of  the  chest.  The 
intercostal  spring  from  the  pleura  and  in- 
tercostal muscles,  accompany  the  intercos- 
tal veins,  pervade  the  internal  dorsal  glands, 
and  terminate  by  several  branches  in  the 
thoracic  duct. 

"  The  lymphatics  of  the  fleshy  part  of 
the  diaphragm  unite,  some  with  the  poste- 
rior intercostal,  others  with  pectoral ;  those 
coming  from  the  crura  run  to  the  dorsal 
glands,  where  they  anastomose  with  the 
intercostal :  those  from  the  cordiform  ten- 
don anastomose  with  the  deep  hepatic,  run 


forward  between  the  layers  of  mediasti- 
num, nearly  to  the  heart,  and  enter  the  car- 
diac glands. 

"  2.  Lymphatics  of  the  Thoracic  Viscera. 
—  The  absorbents  of  the  different  organs 
contained  within  the  thorax  traverse  one  or 
several  of  the  bronchial  or  cardiac  glands, 
and  afterwards  form  divers  branches,  which 
end  in  the  thoracic  duct.  The  pulmonary 
lymphatics,  very  numerous,  are  distin- 
guished into  superficial  and  deep-seated. 
The  first  take  their  rise  from  the  surface  of 
the  lungs,  creep  along  under  their  envelop- 
ing membrane,  and  make  for  one  or  more 
of  the  bronchial  glands.  The  deep  set, 
which  orisfinate  from  the  air-cells  and  from 
the  parenchymatous  tissue,  follow  the  di- 
visions of  the  pulmonary  veins,  run  to  the 
roots  of  the  bronchiae ;  there  unite  with 
the  superficial,  and  perforate  one  or  two  of 
the  bronchial  glands. 

"  The  cardiac  lymphatics  derive  their 
origin  either  from  the  surfaces  (both  exte- 
rior and  interior)  of  the  heart,  or  from  the 
muscular  substance  of  the  organ  ;  they 
mount  upon  the  curvature  of  the  posterior 
aorta,  and  disappear  in  the  cardiac  glands. 

"  The  lymphatics  of  the  superior  part  of 
the  mediastinum,  and  of  the  esophagus, 
join,  some  the  intercostal,  and  others  the 
bronchial ;  those  coming  from  the  anterior 
part  of  this  membranous  partition,  from 
the  thymus,  trachea,  and  esophagus,  unite, 
either  with  the  pectoral,  or  close  with  the 
cardiac  and  anterior  intercostal. 

"  3.  Lymphatics  of  the  Head. —  The 
lymphatics  of  the  head  form  two  planes, 
a  superficial  and  a  deep  one.  The  super- 
ficial pursue  the  course  of  the  cutaneous 
veins,  and  run  in  part  to  the  sublingual 
and  utteral  glands.  The  deep  vessels, 
which  come  from  the  nostrils,  fauces,  palate, 
etc.,  also  run  to  the  gutteral  and  sublingual, 
in  which  they  unite  with  the  superficial. 
From  these  two  groups  of  glands,  through 
which  pass  the  lymphatics  of  the  head,  de- 
part several  large  branches,  two  or  three  of 
which  descend  upon  the  anterior  face  of  the 
trachea;  others  follow  the  course  of  the 
deep-seated  and  cutaneous  veins,  unite  with 


184 


ANATOMY  AND  PHYSIOLOGY  OF  THE  HORSE. 


those  of  the  neck,  and  descend  to  the  front 
of  the  chest.  Ahnost  all  these  vessels  ter- 
minate in  the  thoracic  duct;  some  few 
alone,  on  the  right  side,  ending  in  the  right 
axillary  trunk. 

"4.  Lymphatics  of  the  Left  Fore  Extrem- 
ity.— The  lymphatics  of  this  member  present 
the  same  disposition  as  those  of  the  poste- 
rior limbs,  and  are  divided  into  superficial 
and  deep-seated.  The  former,  consisting 
of  diverse  ramifications,  accompany  the 
superficial  veins ;  the  more  considerable  of 
them  forming  a  plexus,  which  accompanies 
the  cutaneous  (superficial  brachial)  vein 
of  the  limb.  The  deep  vessels  originate 
from  the  foot,  muscles,  and  bones,  pursue 
the  divisions  of  the  deep  veins,  and  plunge 


into  the  axillary  glands,  wherein  they  mite 
with  the  superficial,  and  whence  they  ex- 
tend to  the  thoracic  duct. 

"  The  Right  terminating  Trunk  of  the 
Lymphatics.  —  This  very  short  lymphatic 
canal  is  obliquely  situated  at  the  entrance 
of  the  thorax,  upon  the  transverse  process  of 
the  last  vertebrae  of  the  neck,  extending  in 
a  direction  from  above  downward,  and  from 
without  inward,  and  terminating  most  com- 
monly in  the  right  axillary  vein ;  though,  in 
some  instances,  it  joins  the  thoracic  duct. 
This  trunk  is  formed  by  the  lymphatics 
coming  from  the  right  axillary  glands,  and 
some  from  the  right  lung,  and  right  side  of 
the  neck  and  trachea." 

(See  Appendix.) 


EXAMINATIONS  ON  THE  PHYSIOLOGY  OF   THE   LYMPHATICS. 


Q.  ^Miat  is  the  character  of  the  fluid  found  in  the 
IjTnphatics  ?  —  A.  It  resembles  dilute,  liquor  sanguinis, 
or  the  liquid  portion  of  the  blood  in  -which  the  cor- 
puscles float. 

Q.  What  finally  becomes  of  the  lymphatic  fluid  ?  — 
A.  It  was  formerly  supposed  that  the  lymphatic  fluid 
was  eliminated  from  the  system;  but  Carpenter  and 
other  physiologists  now  contend  that  this  is  not  the 
case ;  that  the  same  is  poured  into  the  common  recep- 
ticle  with  the  nutrient  materials  newly  imbibed  fi-om 
the  food,  whence  both  are  propelled  together  into  the 
general  current  of  the  circulation  ;  and  thus,  instead  of 
being  eliminated,  the  lymphatic  fluid  is  employed  in  the 
formation  of  new  tissues. 

Q.  From  whence  is  the  lymphatic  fluid  derived?  — 
A.  1st,  from  the  residual  fluid,  which,  having  escaped 
from  the  blood-vessels  into  the  tissues,  has  furnished  the 


latter  with  the  materials  of  their  nutrition,  and  is  now 
to  be  returned  to  the  current  of  the  circulation.  2d, 
from  the  25articles  of  the  sohd  frame-work  which  have 
lost  their  vital  powers,  and  are  therefore  unfit  to  be 
retained  as  components  of  the  living  system;  they 
therefore  reenter  the  circulation,  to  be  again  submitted 
to  the  assimulating  jjrocess,  so  that  nothing  shall  be 
lost. 

Q.  By  what  process  do  fluids  enter  the  cutaneous 
Ijinphatics  ?  —  A.  By  a  process  of  imbibation. 

Q.  What  fluid  is  more  readily  absorbed  than  some 
others?  —  ^.  Milk. 

Q.  What  authority  have  you  for  tliis  ?  —  A.  Schoeger, 
in  the  course  of  his  experiments,  found  that  the  lympha- 
tics of  a  limb,  long  immersed  in  milk,  became  tinged 
with  it,  while  none  of  it  could  be  detected  in  blood 
drawn  fi-om  the  veins. 


il0S5arg  at  §tkxmx^  €tt\mMtB. 


24  (185) 


A  GLOSSARY  OF  VETERINAEY  TECHNICALITIES. 


Abdomen.  —  The  posterior  part  of  the  body  of  the  horse. 

Ahdominalis. — Pertaining  to  the  abdomen. 

Abdominal  Regions.  —  The  divisions  of  the  exterior  of 
the  abdomen. 

Abductor.  —  Muscles  are  named  abductors  which  draw 
parts  from  the  axis  of  the  body,  or  given  centres. 

Abnormal.  —  Unnatural,  irregular. 

Accelerator.  —  A  muscle  of  the  penis. 

Acetabulum.  —  A  name  given  to  the  cavity  in  which  the 
head  of  the  thigh  bone  articulates. 

Achillis  Tendo.  —  The  tendon  of  the  muscle  inserted 
into  the  hock. 

Acuminated.  —  Pointed,  like  a  needle. 

Adductor.  —  Muscles  which  draw  parts  toward  the  axis 
of  the  body. 

Adipose.  — Fatty  matter. 

Adventitious.  — Accidental. 

Afferent.  —  A  term  used  to  designate  the  structures 
which  convey  fluids  to  different  parts. 

Aloe. — Wings. 

Albumen.  —  An  element  which  constitutes  the  chief  part 
of  the  white  of  an  egg. 

Alimentary  Canal.  —  The  passage  which  commences  in 
the  oesophagus  and  ends  in  the  anus. 

Alveolus.  —  The  bony  sockets  of  the  teeth. 

Anal.  —  Relating  to  the  anus. 

Anatomy.  —  To  cut,  with  a  view  of  displaying  the  struc- 
ture, relations,  and  uses  of  parts. 

Animus.  — The  principle  of  vitality. 

Annular.  —  A  ring-like  ligament,  found  at  the  posterior 
part  of  the  knee  of  the  horse. 

Antagonist.  —  A  term  applied  to  counteracting  muscles 
or  tendons. 

Anterior. — A  term  applied  to  what  may  be  situated 
before  another  part  of  the  same  kind. 

A7iti.  — A  prefix,  signifying  against. 

Antilabium.  — Against  the  lips. 

Antrum.  —  Cavity  in  bones. 

Anus.  —  The  posterior  extremity  of  the  rectum. 

Aorta.  — The  largest  artery  of  the  body. 

Aortic  —  Pertaining  to  the  aorta. 

Apex.  —  The  pointed  end  of  an  organ. 

Aponeurosis.  —  A  tendinous  expansion  of  fibre. 

Arachnoid.  —  A  membrane  of  the  brain. 

Arch  of  the  Colon.  — Transverse  portion  of  that  intestine. 

Areola.  —  The  spaces  between  fibres  composing  an 
organ. 

Arterial.  —  A  property  belonging  to  arteries. 

Arterialization.  —  The  change  which  occurs  in  venous 
blood  when  brought  in  contact  with  air  in  the  lungs. 

Artery.  —  The  name  of  blood-vessels  which  distribute 
arterial  blood. 


Anicular.  — Belonging,  or  relating,  to  joints. 

Articulation.  —  (From  articulus.)     A  joint. 

Asperity.  —  A  roughness. 

Astragalus.  —  The  bone  beneath  the  os  calcis. 

Atlas.  —  The  anterior  bone  of  the  neck. 

Attollens.  —  A  name  given  to  muscles  which  lift,  or  raise, 
the  parts. 

Auditory.  —  Muscles  and  parts  connected  with  the  ear. 

Auricular.  —  Relating  to  the  ear. 

Auricles. —  The  anterior  cavities  of  the  heart. 

Axilla.  —  The  part  between  the  superior  region  of  the 
arm  and  the  chest. 

B. 

Biceps.  —  (From,  bis  —  twice,  and  caput — a  head ;  two 
heads.)  The  term  is  applied  to  muscles,  having  two 
distinct  heads,  or  origins. 

Bifurcate.  —  (Bifurcas  ;  from  bis,  twice,  and  furca,  a 
fork).  A  blood-vessel  or  muscle  is  said  to  bifurcate  when 
it  divides  into  two  branches. 

Bilary.  —  Relating  to  the  bile. 

Brachial.  —  Of,  or  belonging,  to  the  arm. 

Bronchia.  — Bifurcations  of  the  windpipe. 

Bronchial.  —  Relating  to  the  bronchia. 

Buccal.  —  (From  bucca,  the  cheek.)  Belonging  to  the 
cheek. 

Buccinator.  —  A  muscle  of  the  cheek. 

Bulb.  —  A  dilated  portion  of  the  tube  at  the  base  of  the 
penis. 

Bursce.  —  Sacs,  or  bags. 

Bursoe  Mucosce.  —  Sacs  found  in  the  region  of  joints. 

Bursal.  —  Relating  to  bursas. 

C. 

Ccecum.  —  The  blind  gut. 

Ccecal.  —  Pertaining  to  the  caecum. 

Calcis  Os.  —  The  prominent  bone  of  the  hock. 

Cancelli.  —  Cellular  structure  of  bones. 

Canine  Teeth.  —  The  eye-teeth,  cuspidati. 

Canthus.  —  The  angle  of  the  eye. 

Capillary.  —  Hair-like  vessels  which  are  found  between 
the  arterial  and  venous  vessels. 

Capstde. — A  membranous  sac. 

Capsular.  —  A  term  applied  to  ligaments  which  surround 
articulations. 

Caput.  —  The  head. 

Cardia.  —  The  heart. 

Cardiac.  —  Pertaining  to  the  heart. 

Carotid.  —  The  name  of  the  principal  arteries  of  the 
neck. 

Carpus.  —  The  bones  of  the  knee . 

Caruncle.  —  A  small  fleshy  excrescence. 

CarunculcE  Lacrymalis.  —  Small  fleshy  bodies  found  in 
the  angle  of  the  eye. 

(187) 


.188 


GLOSSARY  OF  VETERINARY  TECHNICALITIES. 


Cauda.  — The  tail. 

Cara.  —  The  largest  vein  in  the  body  of  the  horse. 

Cavity.  —  A  hollow  part;  the  abdominal  cavity,  for 
example. 

Cellular .  —  Composed  of  cells. 

Centrum  Ovale.  —  The  appearance  of  the  brain,  when  a 
horizontal  section  is  made  on  a  level  with  the  corpus  cal- 
losum. 

Centrum  Tendinosum.  —  Tendinous  centre  of  the  dia- 
phragm. 

Cephalic.  —  Pertaining  to  the  head. 

Cerebellum.  —  Inferior  lobe  of  the  brain. 

Cerebrum.  —  Superior  lobe  of  the  brain. 

Cerebral.  —  Relating  to  the  brain. 

Cerebrospinal.  —  Pertaining  to  both  the  brain  and  spinal 
cord. 

Cervical.  —  Pertaining  to  the  neck. 

Cervix.  —  The  neck  or  contracted  portion  of  an  organ. 

Choree  Tending.  —  Part  of  the  internal  structure  of  the 
heart. 

Choroid.  —  The  inner  tunic  of  the  eye. 

Chyle.  —  A  fluid  found  in  the  thoracic  duct  and  lacteals. 

Chyme.  —  A  name  given  to  the  food  after  it  has  passed 
the  pylorus. 

Cilia.  —  The  eyelids,  hair  of  the  same,  etc. 

Cineritious.  —  A  term  applied  to  that  part  of  the  brain 
which  is  of  an  ash  color. 

Circulus.  —  A  ring. 

Clitoris.  —  A  part  of  the  pudendum  of  the  mare  corres- 
ponding to  the  glans  penis  of  the  horse. 

Coccyx.  —  The  bones  of  the  tail. 

Cochlea.  —  The  spiral  cavity  of  the  car. 

Caecum.  —  (Sometimes  spelt  cajcum.)   The  blind  gut. 

Ccdiac.  —  Prolongation  of  the  solar  plexus,  an  artery 
and  vein  of  the  abdomen. 

Colon.  —  The  largest  and  most  dilated  portion  of  the 
intestines. 

Columnar  Carna.  —  A  muscular  arrangement  within  the 
cavity  of  the  heart. 

Commisure.  —  A  suture,  junction,  or  joint. 

Complexus.  —  To  embrace  or  surround. 

Concha.  —  External  cavity  of  the  ear. 

Conduit.  — A  canal. 

Condyle. — An  irregular  process  or  enlargement. 

Condyloid. — A  tubercle,  ■\vart-like. 

Conglobate.  —  Ball-shape. 

Conglomerate.  —  An  assemblage  of  glands. 

Conjunctivia.  —  External  coat  of  the  eyeball,  and  inter- 
nal lining  of  the  eyelids. 

Conoid.  —  Cone-like. 

Constrictor.  —  Muscles  that  are  bound  together  ai'e  thus 
named.     The  office  is  to  close  an  outlet. 

Continuity.  —  Identity  of  parts,  having  direct  connection. 

Convolute.  —  Rolled  up. 

Coracoid.  —  Like  a  crow's  beak  ;  a  process  of  the 
scapula. 

Cornea.  —  Anterior  coat  of  the  eye. 

Cornu.  —  A  horn. 

Corona.  —  A  crown,  the  superior  pastern  is  thus  named : 
OS  coronte. 

Coronal  Suture.  —  The  uniting  medium  between  the 
frontal  and  parietal  bones. 

Coronary.  — Arteries  and  veins,  proper  to  the  heart,  are 
thus  named 


Coronoid.  —  Processes  of  bones  arc  thus  named  when 
they  form  an  eminence. 

Corpora.  — A  term  applied  to  numerous  prominences  in 
the  brain  and  elsewhere. 

Corpus.  —  A  body. 

Corpora  Striata.  —  Striped  eminences  in  the  brain. 

Corpuscle.  —  A  minute  body. 

Corrugator.  —  A  muscle  which  wrinkles  the  surrounding 
parts. 

Cortical.  —  Resembling  bark. 

Costa.  —  A  rib. 

Costal.  —  Pertaining  to  the  region  of  the  ribs. 

Costalis  Pleura.  —  That  portion  of  the  pleura  which 
lines  the  interior  of  the  chest. 

Cotyloid.  —  Cup-shaped. 

Cranium.  —  The  skull. 

Crassamentum.  —  The  clot,  or  red  globules,  of  the  blood. 

Cremaster.  —  A  muscle  of  the  testicle. 

Crest  of  the  Ileum.  —  The  anterior,  superior  parts  of  the 
pelvis. 

Cricoid.  —  Ring-like. 

Crista.  —  A  crest. 

Crucial.  —  In  the  form  of  a  cross. 

Crural.  —  Relonging  to  the  thigh. 

Crystalloid.  —  Resembling  a  crystal. 

Cuboides.  —  One  of  the  bones  of  the  knee,  which  resem- 
bles a  cube,  or  die. 

Cuneiforme. — A  bone  of  the  knee,  in  form  resembling  a 
wedge. 

Cuspidata.  —  The  tushes  of  the  horse  are  thus  named. 

Cutaneous.  —  Belonging  to  the  skin. 

Cuticle.  —  The  scarf  skin. 

Cyst.  —  A  bladder  or  sac. 
D. 

Dartos.  —  A  name  given  to  the  muscle  which  corrugates 
the  scrotum. 

Defei-ens.  —  The  excretory  canal  of  the  testes. 

Dentatus.  —  A  tooth-like  process  on  the  second  cervical 
vertebra. 

Denies  Incisors.  —  The  twelve  front  teeth  of  the  horse. 

Dentes  Molares.  —  The  twenty-four  grinders. 

Depressor.  —  A  muscle  is  so  named  when  it  depresses 
the  part  on  which  it  acts. 

Diaphragm.  —  The  muscle  which  separates  the  thorax 
from  the  abdomen. 

Diastole. — Periodic  dilation  of  the  heart. 

Dilator.  —  A  name  given  to  muscles  which  dilate  certain 
parts. 

Diploe.  —  The  cellular  structure,  which  separates  bony 
tablets. 

Diverticulum.  —  A  blind  tube,  diverging  from  the  course 
of  a  larger  one. 

Dorsal.  —  Pertaining  to  the  back. 

Ducts.  —  Orifices  of  various  canals. 

Ductus.  —  A  canal  for  conveying  fluids. 

Duplicate.  — Doubled. 

Duplicature.  —  Reflection  of  a  membrane  upon  itself. 

Dura  Mater.  —  The  outermost  tunic  of  the  brain. 


Efferent.  —  Vessels  are  thus  named  which  convey  fluids 
from  glands. 

Elevator.  —  A  muscle  is  so  called  when  it  lifts  or  elevates 
the  parts  to  which  it  is  attached. 


GLOSSARY   OF  VETERINARY  TECHNICALITIES. 


189 


Encephalon.  —  The  brain, 

Ensiform.  —  Sword-like. 

Epididymis. — An  appendage  to  the  testicle. 

Epigastrium. — Region  of  the  stomach. 

Epiglottis.  —  Cartilage  at  the  root  of  the  tongue. 

Epiphysis. — A  union  of  bones  by  means  of  cartilage. 

Epithelium.  —  Atransparent  membrane  covering  various 
internal  parts. 

Erector.  —  A  name  given  to  certain  muscles,  which  raise 
or  erect  the  parts. 

Eroded.  —  Rough  and  jagged. 

Esophagus.  —  The  gullet. 

Ethmoid.  —  Sieve-Hke. 

Ecito-Motary.  —  The  trae  spinal  nerves. 

Excretory.  —  Vessels  and  ducts  are  thus  named  which 
discharge  fluids. 

Expiration.  —  The  act  of  expelling  air  from  the  lungs. 

Extensor.  —  To  stretch  out;  a  name  given  to  several 
muscles  and  tendons. 

Extremity.  —  The  end. 

F. 

Facial.  —  Belonging  to  the  face. 

Falciform. —  Scythe-shaped. 

Falx.  —  The  scythe  process  of  the  dura  mater. 

Fascia.  —  The  tendinous  expansion  of  muscles. 

Fascicular.  —  Fibres  arranged  in  bundles. 

Fauces. — Posterior  part  of  the  mouth. 

Femoral.  —  Of,  or  belonging  to,  the  thigh. 

Fenestra.  —  Part  of  the  internal  ear. 

Fibre. — A  thread  or  filament. 

Fibrous.  —  Composed  of  fibres. 

Fibula. — A  small  bone  attached  to  the  posterior  part  of 
the  tibia  of  the  horse. 

Filament. — A  minute  fibre. 

Filiform.  —  Thread-like. 

Fimbria. — A  fringe. 

Fissure.  —  A  crack  or  groove. 

Flavus.  —  Yellow. 

Flexor.  —  A  name  given  to  numerous  muscles  and  ten- 
dons which  bend  the  limbs. 

Foliatus.  —  Leaf-form. 

Follicle.  —  A  minute  sac  or  bag. 

Foramen.  —  An  opening. 

Fornex.  —  Arch  or  vault ;  one  of  the  structures  of  the 
brain. 

Fossa.  —  A  shallow  cavity  or  depression. 

Frcenum.  —  A  ligament  which  restrains  motion. 

Frontal.  —  Belonging  to  the  anterior  part  of  the  cranium. 

Function.  —  Any  action  by  which  vital  phenomena  are 
produced. 

Fundus.  —  The  base  or  bottom. 

Funis.  —  The  umbilical  cord. 

G. 

Ganglion.  —  A  knot  or  enlargement  in  the  course  of  a 
neiwe. 

Gastric.  —  Pertaining  to  the  stomach. 

Gastric  Juice.  —  A  secretion,  peculiar  to  the  walls  of  the 
stomach. 

Gastrocnemii.  —  The  tendinous  portion  of  muscles  in- 
serted into  the  os  calcis,  or  point  of  the  hock,  are  thus 
named. 

Gemini.  —  T^vins  :  two  organs  precisely  alike  arc  thus 
named. 


Gestation. — Pregnancy. 

Gland.  —  An  organ  of  secretion. 

Glandula.  —  A  small  gland. 

Glandular.  —  Resembling  a  gland. 

Glenoid.  —  The  name  of  articulating  cavities. 

Glissons  Capsule.  —  The  fibrous  envelope  of  the  liver. 

Globate.  —  Globe-like. 

Globules.  —  Red  particles  of  the  blood. 

Glohuline. — Albuminous  constituent  of  the  blood. 

Glomerate.  —  Congregated. 

Glossa.  —  The  tongue. 

Glottis.  —  Upper  opening  into  the  windpipe. 

Gluteal. — Belonging  to  the  haunch. 

Gracilis.  —  A  muscle  on  the  inner  part  of  the  thigh. 

Granule.  — A  small  grain. 

Gutteral.  —  Belonging  to  the  throat. 

H. 

Hepatic.  —  Belonging  to  the  liver. 

Hiatus. —  An  aperture  or  foramen. 

Hippo. — A  horse ;  a  prefix. 

Hippocampus.  —  Two  eminences  in  the  Lateral  ventricles 
of  the  brain. 

Homo.  —  A  prefix  designating  similarity. 

Humerus.  —  The  bone  beneath  the  shoulder  blade. 

Hyo.  —  Names  compounded  with  this  prefix  relate  to 
muscles  situated  near  the  root  of  the  tongue. 

Hyoides. — Bone  at  the  root  of  the  tongue. 

Hypochondrium.  —  A  region  of  the  abdomen. 

Hypogastric.  —  Relating  to  the  hypogastric  region  of  the 
abdomen. 

I,  J. 

Meo.  —  A  prefix,  the  ileum  or  bone  of  the  pelvis. 

Ileum.  —  A  portion  of  the  intestinal  tube. 

Iliac.  —  Region  of  the  flanks. 

Incisors.  —  The  twelve  front  teeth,  or  nippers,  of  the 
horse  are  thus  named. 

Incus.  —  A  bone  of  the  ear. 

Infra.  —  Under ;  aprefix  to  tiie  name  of  several  muscles. 

Infra.  — Without. 

Infundibulum.  —  A  funnel  or  duct. 

Inguinal.  —  Pertaining  to  the  groin. 

Inguinal  Ligament.  — Pouparts  ligament. 

Innominatum.  —  Without  a  name. 

Innominatum  Os.  —  Union  of  the  ileum,  ischium,  and 
pubic  bones. 

Inosculation.  —  Union  of  the  extremities  of  vessels. 

Insertion.  —  Attachment  of  a  muscle  or  tendon  to  the 
part  which  it  moves. 

Integumeyits.  —  The  skin  and  sub-tissures. 

Inter  articular.  —  Between  the  joints. 

Interosseous.  —  Muscles  and  ligaments  situated  between 
bones  are  thus  named. 

Interseptum.  —  The  uvula. 

Interstitial.  —  A  term  applied  to  substances  occupying 
the  spaces  between  contiguous  parts. 

Inter spinales. — Between  the  spines  of  bones. 

InteHransver sales. — Muscles  located  between  the  trans- 
verse processes  of  bones. 

Intervertebral.  —  The  articular  cartilages  between  the 
vertebras  are  thus  named. 

Intestinal  Canal.  —  The  interior  of  the  duodenum,  jeju- 
num, ileum,  cajcum,  colon,  and  rectum,  comprises  the  in- 
testinal canal. 


190 


GLOSSARY   OF   VETERINARY  TECHNICALITIES. 


Intra.  —  Within. 
Intestines.  —  The  bowels. 

Invertebrata. — Animals  without  internal  bony  structure. 
Ischium.  — A  part  of  the  bones  of  the  pelvis. 
Isthmus.  —  A  narrow  passage. 

Jejunum.  —  A  term  applied  to  that  portion  of  the  intes- 
tine which  is  generally  found  empty. 
Jugular.  —  Belonging  to  the  neck. 

L. 

Lahorium.  —  Relating  to  the  lips. 

Labia.  —  The  lips. 

Lachryma.  — A  tear. 

Lachrymal.  —  Structures  concerned  in  the  secretion  and 
transmission  of  tears. 

Lacteals.  —  Absorbent  vessels  of  the  IjTnphatics. 

Lactiferous.  —  Vessels  conveying  milk. 

Lacunce. — Ducts  issuing  from  small  glands. 

Lamella.  —  Thin  plates. 

Lamince.  —  A  series  of  plates. 

Laminated.  —  Leaf-like. 

Laryngeal.  — Relating  to  the  larynx. 

Larynx.  —  The  superior  part  of  the  windpipe. 

Lata.  —  Broad. 

Lateral.  —  Pertaining  to  the  side. 

Latissimus.  —  A  term  applied  to  a  muscle  in  consequence 
of  its  great  breadth. 

Lens.  —  A  crystalline  body ;  a  lentil. 

Lenticular.  —  Shaped  like  the  lens. 

Levator.  —  A  term  applied  to  muscles  which  raise  the 
parts  to  which  they  are  attached. 

Ligament.  —  A  tendinous  cord. 

Linea.  —  A  white  line  ;   thread-like. 

Linea  Aspera.  — A  rough  projection. 

Linea  Semilunares,  or  semi-circularis. — Lines  on  each 
side  of  the  linea  alba,  formed  by  the  termination  of  the 
fibres  of  the  abdominal  muscles. 

Linea  Transversalis.  —  Lines  crossing  the  recti  muscles 
of  the  abdomen. 

Lingual.  —  Pertaining  to  the  tongue. 

Lingualis.  —  A  muscle  of  the  tongue. 

Liquor  Sanguinis.  —  The  fluid  element  of  the  blood. 

Lobe.  —  A  division  of  an  organ. 

Lobus.  —  A  lobe. 

Local.  —  Confined  to  a  part. 

Loins.  —  The  posterior  part  of  the  back. 

Longissimus.  —  The  longest. 

Longus.  —  Long,  lengthy. 

Lumbar.  —  Belonging  to  the  loins. 
Lumbrici.  —  Worms. 

Luna.  —  The  moon. 

Lunare.  —  A  bone  of  the  knee. 

Lymph.  —  A  fluid  found  in  the  lymphatics. 
Lymphatic.  —  Of  the  nature  of  lymph. 

M. 

Major.  —  The  greater. 
Malar. — Belonging  to  the  cheek. 
Malleus.  —  A  hammer  or  mallet. 
Malphigian  Bodies.  —  Dark  points  of  the  kidneys. 
Mamma.  —  The  udder. 
Mammary.  —  Belonging  to  the  uddei'. 
Masseter.  — A  muscle  of  the  jaw. 
Mastoid.  —  Processes  of  bones  presenting  the  form  of  a 
nipple  are  thus  named. 


Mater.  —  A  mother. 

^farilla.  —  Bones  of  the  jaw. 

Maxillary.  —  Pertaining  to  the  jaw. 

Meatus.  —  A  passage. 

Meatus  Urinarius.  —  The  internal  auditory  passage  of 
the  ear. 

Meatus  Urinorions.  —  The  orifice  of  the  urethra. 

Median.  — Central,  the  central  line. 

Mediastinum.  — The  partition  which  divides  the  thorax. 

Medulla.  —  The  medullary  substance  of  the  brain  is  thus 
named.   It  signifies  marrow  or  pith. 

Medulla  Spinalis.  —  The  spinal  marrow. 

Membranes.  —  Tissues. 

Membranous.  —  Having  the  texture  of  membranes. 

Meninges.  —  Membranes  of  the  brain. 

Meningial.  —  Relating  to  the  membranes  of  the  brain. 

Mesenteric.  —  Pertaining  to  the  mesentery. 

Mesentery.  —  Membranes  uniting  the  intestines. 

Mesian  Line.  —  The  middle  line. 

Mesa.  —  Words  compounded  of  meso  signify  the  middle. 

Metacarpal.  —  Relating  to  the  knee  of  the  horse. 

Metacarpus.  —  The  bones  of  the  knee. 

Molar.  —  The  grinders. 

Motor.  —  To  move ;  the  nerves  of  voluntary  motion  are 
thus  named. 

Mucus.  —  Animal  mucilage. 

Mucous.  —  A  term  applied  to  the  mucous  tissues. 

Muscular.  — Belonging  to  a  muscle. 

Muscle.  —  Flesh;  a  bundle  of  muscular  fibres. 

Mylo.  —  Names  compounded  of  this  word  relate  to 
muscles  located  in  the  region  of  the  root  of  the  tongue. 

Myology.  — A  description  of  the  muscles. 

N. 
Nares.  —  The  anterior  canity  of  the  nostrils. 
Nasal.  —  Belonging  to  the  nose. 
Navicular.  —  Boat-shaped. 
Neurilema.  —  The  sheath  investing  the  nerves. 
Nidus.  —  Naked. 

Nucha. — A  part  of  the  superior  region  of  the  neck. 
Nucha  Ligamentum.  — A  ligament  of  the  spine. 
Nympha.  —  Internal  labise  of  the  vulva. 

O. 

Oblique.  —  A  term  applied  to  muscles  that  have  an 
oblique  direction. 

Obturator.  —  Name  of  muscles,  foramina;,  etc. 

Occipital.  —  Connected  with  the  occiput  or  posterior 
part  of  the  cranium. 

Occipito  Atloid.  —  That  which  has  reference  to  the  occi- 
put and  alias. 

Occipito  Frontalis.  —  A  muscle  which  reaches  from  the 
occiput  to  the  forehead. 

Ocidar.  —  Belonging  to  the  eye. 

Odontoid.  —  Tooth-like. 

Oesophagus.  —  The  gullet. 

Olecranon.  —  Point  of  the  arm,  formed  by  the  ulna. 

Olfactory.  —  Relating  to  the  sense  of  smell. 

Olivaris.  —  Resembling  the  olive. 

Omentum.  —  The  caul. 

Omo.  —  Names  compounded  of  this  word  signify  mus- 
cles which  are  attached  to  the  scapula. 

Opaque.  —  Not  transparent. 

Optic.  —  Relating  to  vision. 


GLOSSARY  OF  VETERINARY  TECHNICALITIES. 


191 


Orbicular.  —  Spherical-circular. 

Orbicularis  Oris.  —  Muscle  of  the  lips. 

Orbicularis  Palpebrarum.  —  Muscle  of  the  eyelids. 

Orbiculare.  —  The  smallest  bone  of  the  internal  ear. 

Orbit.  —  The  bony  socket  of  the  eye. 

Orbitar.  —  Pertaining  to  the  orbit. 

Organ.  —  A  part  having  a  distinct  office  to  perform. 

Organism.  —  Vital  organization. 

Organized.  —  Possessed  of  organs ;  endowed  with  life. 

Orijice. — An  apeiture. 

Origin.  —  The  fixed  point  or  commencement  of  a  muscle. 

Os.  —  A  bone. 

Osseous.  —  Bony. 

Ovaria.  —  The  female  testes. 

Ovum.  —  An  egg. 

P. 

Palatine.  —  Relating  to  the  palate. 

Palate.  —  The  roof  of  the  mouth. 

Palate  Os.  —  Bone  of  the  palate. 

PalpebrcE.  —  The  eyelids. 

Paries.  —  A  wall. 

Parietes.  —  The  walls  of  the  abdomen  and  thorax,  etc. 

Parotid.  —  Name  of  the  gland  beneath  the  ear. 

Parotid  Duct.  —  Opening  into  the  cheek  from  the  parotid 
gland. 

Patella.  —  The  stifle  bone. 

Pectinated.  —  Shaped  like  the  teeth  of  a  comb. 

Peduncle,  —  A  stalk. 

Pellicle.  —  A  thin  membrane. 

Pelvis.  —  The  cavity  formed  by  the  innominata  and 
sacrum. 

Penis.  —  The  principal  organ  of  generation  in  the  male. 

Perforans.  —  Perforating ;  the  name  of  part  of  the  flexor 
tendons. 

Perforatus.  —  Perforated  for  the  transmission  of  the 
preceding  tendon. 

Peri.  —  Around  an  envelope. 

Pericardium.  —  The  sac  containing  the  heart. 

Pericranium.  —  The  membrane  investing  the  skull. 

Perineum.  —  The  part  between  the  anus  and  organs 
of  generation. 

Periosteum.  —  Membrane  investing  bones. 

Periphery.  —  The  circumference. 

Peritoneum.  —  The  serous  membrane  which  lines  the  in- 
terior of  the  abdomen  and  is  reflected  on  its  contents. 

Peroneal.  —  Relating  to  the  fibula. 

Petaloid.  —  Shaped  like  a  petal. 

Petrosum  Os.  —  Rough  portion  of  the  temporal  bone. 

Peyer's  Glands.  —  Clustered  mucous  glands  of  the  in- 
testines. 

Pharyngial.  —  Relating  to  the  pharynx. 

Pharynx.  —  Superior  part  of  the  gullet. 

Phrenic.  —  Belonging  to  the  diaphragm. 

Pia  Mater. — A  thin  membrane  investing  the  brain. 

Pigmentum  Nigrum.  —  Black  pigment  upon  the  choroid 
coat  of  the  eye. 

Pilus.  —  Hair. 

Pineal.  —  Shaped  like  the  fruit  of  the  pine. 

Pisiform.  —  Shaped  like  a  pea. 

Pituitary  Membrane.  —  The  sclmeiderian  membrane  of 
the  nostrils. 

Placenta.  —  The  afterbirth. 

Plantar.  —  Relating  to  the  feet. 


Pleura.  —  The  serous  membrane  which  lines  the  cavity 
of  the  chest,  and  is  reflected  on  the  contents  of  the  same. 

Plexus.  —  A  network  of  nerves  or  vessels. 

P^zca.  — A  fold. 

Pons.  —  A  bridge. 

Pons  Varolii.  —  A  part  of  the  brain. 

Popliteal.  —  Muscles,  nerves,  and  vessels  in  the  region 
of  the  hock. 

Pores.  —  Extremities  of  the  exhalents  of  the  skin. 

Porta. — A  door  or  gate. 

Portio.  —  A  portion  or  branch. 

Posterior.  — Behind. 

Posticus.  —  Situated  behind. 

Pracordia.  —  The  anterior  part  of  the  chest. 

Primce  Vice.  —  First  passages  of  the  alimentary  canal. 

Process.  —  The  projecting  eminence  on  a  bone. 

Profundus.  —  Deep-seated. 

Pronatus.  —  Muscles  of  the  foi*e  limbs. 

Prostate.  —  A  gland  near  the  neck  of  the  male  bladder. 

Pseudo.  — False ;  a  term  applied  to  spurious  membranes. 

Psoce.  —  The  loins. 

Psoas.  —  Belonging  to  the  loins. 

Pterygoid.  —  Shaped  like  a  ^sing. 

Pubes.  —  The  junction  of  the  pelvic  bones  at  their  in- 
ferior parts. 

Pubic.  — Pertaining  to  the  pubes. 

Pudendum. — The  external  parts  of  the  female  organs 
of  generation. 

Pudic.  —  Belonging  to  the  pudenda. 

Pulmonary.  — Belonging  to  the  lungs. 

Puncta.  —  Lachrymalia.  The  tear-ducts  within  the  eye- 
lids. 

Punctum.  —  A  point. 

Pylorus.  —  The  outlet  of  a  horse's  stomach. 

Pyriforrfl.  —  Shaped  like  a  pear. 

Q- 

Quadratus.  —  Square  in  form  or  figure. 

R. 

Radial.  —  Belonging  to  the  radius. 
Radiated. —  Diverging  from  the  centre  like  the  sun's  rays. 
Radicles.  —  Germs  of  the  roots. 
Radius.  —  Bone  of  the  fore  extremity. 
Ramify.  — To  branch  out,  or  from. 
Ramose.  —  Branched. 
Ramus.  —  A  branch. 
Ranine.  — Vessels  under  the  tongue. 
Rapce.  —  The  central  line  of  the  scrotum. 
Rectum.  — The  posterior  termination  of  the  intestines. 
Rectus.  —  Straight. 

Recurrent.  —  Running  in  a  backward  ditection. 
Reflection.  —  A  duplicature. 
Regions.  —  Divisions  of  the  body. 
Renal.  —  Belonging  to  the  kidneys. 
Rete.  —  Net-work. 
Retiform.  —  Net  like. 
Retina.  —  Expansion  of  the  optic  nerve. 
Retractor.  —  Muscles  thus  named  draw  backwards. 
Retrahens.  —  Drawing  back. 
Rima.  — An  opening  or  fissure. 

Rotator. — A  name  given  to  muscles  that  rotate  or  re- 
volve a  part. 
Rotundus.  —  Circular,  round. 


192 


GLOSSARY   OF   VETERINARY   TECHNICALITIES. 


Ruga.  — A  wrinkle. 
Rugose,  —  "Wrinkled. 


S. 


Sac.  —  A  bag  or  cyst. 

Saculated.  —  Encysted. 

Sacral.  —  Belonging  to  the  sacrum. 

Sjgittah  —  Arro-sv-shaped. 

Saliva)-!/.  —  Eclating  to  the  saliva 

Sanguis. — Blood. 

Saphena.  — A  vein  of  the  hind  extremities. 

Scaphoid.  —  Shaped  like  a  boat. 

Scapula.  —  Shoulder  blade. 

Scrotal.  — Relating  to  the  scrotum. 

Scrotum.  —  The  sac  in  ■which  the  testicles  are  con- 
tained. 

Sebaceous.  —  Resembling  suet. 

Secernent.  —  Secretory. 

Semen.  — Secretion  peculiar  to  the  testes. 

Semi.  —  One-half. 

Septum. — Apartition  or  division. 

Serrated.  —  Resembling  the  teeth  of  a  saw. 

Serum.  —  The  fluid  portion  of  the  blood. 

Sessamoid.  — Like  seeds. 

Sigmoid.  —  Flexure. 

Sineio.  — A  tendon. 

Sinus.  —  A  long  cavity. 

Spermatic.  — Belonging  to  the  testicles. 

Sphenoid.  —  Wedge-like. 

Sphenoidal.  —  Belonging  to  sphenoid  bono. 

Sphincter.  —  Curcular  muscles,  which  close  an  opening, 
are  thus  named. 

Spinal.  —  Belonging  to  the  spine. 

Spinal  Marrow.  —  Medulla  spinahs. 

Spine.  —  The  vertebral  column. 

Spinus.  —  Thorn-like. 

Splanchic.  — Belonging  to  the  intestines. 

Squamous.  —  Resembling  scales. 

Stapes.  —  A  stirrup  ;  bone  of  the  ear. 

Sternal.  —  Belonging  to  the  breast  bone. 

Sternum.  —  Breast  bone. 

Striated.  —  Marked  with  long  lines. 

Styloid.  —  Shaped  like  a  pointed  pencil. 

Sub. — Under;  beneath. 

Sublimus.  —  This  term  is  applied  to  a  muscle  when 
ceated  more  superficially  than  another  of  the  same  kind. 

Sublingual.  —  Beneath  the  tongue. 

Submaxillar)/.  — Under  the  inferior  jaw. 

Subscapular.  —  Liner  side  of  the  shoulder  blade. 

Super.  —  Above. 

Superficial. — Upon  or  near  the  surface. 

Superior.  —  The  upper  part. 

Suture.  —  Jimction  or  union. 

Sympathetic.  — Associated  in  function. 

Symphysis.  —  A  connection  of  bones  by  an  intervening 
substance. 

Synovia.  —  The  lubricating  fluid  of  joints,  sometimes 
called  joint-oil. 

Systole.  —  Contraction  of  the  heart. 

T. 
Tabula.  —  An  extended  surface. 
Tarsus.  —  The  hock. 
Tegumentary.  —  Relating  to  the  skin. 
Temporal.  —  Relating  to  the  temporal  regions  of  the 
cranium. 


Tendon.  — The  extremity  of  a  muscle. 

Tcndo  Achillis.  —  The  tendon  of  the  gastrocnemii,  in- 
serted into  the  hock. 

Tensor.  —  A  name  given  to  muscles  which  stretch  or  ex- 
tend parts. 

Toitorium.  — A  membranous  partition  of  the  brain. 

Teres.  —  Round ;  cylindrical. 

Testes.  —  The  testicles. 

Thalami  Nervorum  Opticorum.  —  Supposed  origin  of 
the  optic  nerves. 

Thalamus. — A  bed  or  origin  of  certain  parts. 

Theca. — A  sheath. 

Thoracic.  —  Belonging  to  the  thorax  or  chest. 

Thoracic  Duct.  —  The  ti-unk  of  the  absorbents. 

Tliorax.  —  The  chest. 

Thjro. — Names  compounded  with  this  word  belong 
to  muscles  which  are  attached  to  the  thyroid  cartilage. 

Thyroid.  —  Resembling  a  shield. 

Tibia.  —  The  bone  beneath  the  femur. 

Tibial.  —  Belonging  to  the  tibia. 

Tinea.  —  The  name  of  a  fish ;  the  tench. 

Tissue.  —  An  organized  structure. 

Trachea.  —  The  windpipe. 

Tmcheal.  —  Pertaming  to  the  windpipe. 

Trachelo.  —  Names  compounded  with  this  word  belong 
to  muscles  located  in  the  region  of  the  neck. 

Transversalis.  —  Having  a  transverse  direction. 

Transversus.  —  Placed  across. 

Trapezium.  —  A  four-sided-figure,  bone  of  the  horse's 
knee. 

Trapezoides.  —  A  bone  which  in  figure  somewhat  re- 
sembles the  preceding ;  it  also  enters  into  the  composition 
of  the  horse's  knee. 

Trapezius.  —  Four  square ;  a  muscle  placed  over  the 
region  of  the  withers. 

Triangularis.  —  Triangular. 

Triceps.  —  Three-headed. 

Tricuspid.  —  Having  three  points  ;  a  name  applied  to 
a  valve  in  the  right  ventricle. 

Trifid.  —  Three-cleft. 

Trigastric.  — Having  three  bellies. 

Trisplanchic  Nerve.  —  The  great  sympathetic  or  gan- 
glionic nerve. 

Trochanter.  —  Eminences  or  tuberosities  on  the  bones. 

Tuba.  —  A  tube. 

Tuber.  —  A  solid  roundish  substance. 

Tuberosity.  —  Protuberance  or  projection. 

Tubular.  —  Tube-like. 

Tunic.  —  A  membranous  covering. 

Turbinated.  —  Shaped  like  a  sugar-loaf. 

Turgid.  —  Swollen. 

U. 

Ulna. — Bone  of  the  fore  extremity,  termed  point  of 
the  elbow. 

Ulnar.  —  Pertaining  to  the  ulna. 

Unibilicus.  —  The  navel. 

Unciform.  —  Shaped  like  a  hook. 

Ureter.  —  A  tubular  connection  between  the  kidneys 
and  bladder. 

Urinal.  —  Pertaining  to  the  urine. 

Uterine.  —  Relating  to  the  womb. 

Uterus.  —  The  womb. 

Uvula.  —  A  pendulous  body,  posterior  to  the  soft  palate. 


GLOSSARY   OF   YETERINARY  TECHNICALITIES. 


193 


Vagina.  —  A  sheath;  the  cavity  between  the  pudenda 
and  womb. 

Vaginal.  —  Pertaining  to  the  vagina. 

Valvular. — Valve-like. 

Vas.  —  A  vessel. 

Vas  Deferens.  —  Excretory  duct  of  the  testicle. 

Vasa.  —  The  plural  of  vas ;  vessels. 

Vascular.  —  Highly  organized  with  blood-vessels. 

Vascular  System.  —  The  heart  and  its  vessels. 

Vastus.  —  Relates  to  size;  large,  thick  and  fleshy  mus- 
cles of  the  thigh. 

Vena. — A  vein. 

Vena  Cava.  —  The  great  vein. 

Vena  Porta.  —  The  largest  vein  of  the  liver. 

Venter.  —  The  belly. 

Ventricles. — A  term  applied  to  the  cavities  of  the  brain 
and  heart. 

Vermiform.  —  Shaped  like  a  worm. 

Verlebrce.  —  Bones  of  the  spinal  column: 

Vesical.  —  Formed  like  a  bladder;  pertaining  to  the 
bladder. 


Vesicles  Graaffian.  —  Small  bladders  or  cysts  found  in 
the  ovaria  (female  testes). 

Via.  —  Way  or  passage. 

Villous.  —  Velvet-like,  applied  to  the  villous  coat  of  a 
horse's  stomach. 

Viscera.  —  Internal  organs. 

Visceral.  —  Relating  to  a  viscus. 

Viscus. — An  organ  within  the  body. 

F/ta/.  — Life-like. 

Vitreous.  —  Glassy ;  transparent. 

Vivisection.  —  Surgical  operations  on  living  subjects. 

Vivus.  —  Living ;  life-like. 

Vulva.  —  The  pudendum. 

Z. 

Zoology.  —  The  science  of  animals. 
Zootherapeutics.  —  Relates  to  the  curative  action  of  med- 
icines. 
Zootomy.  —  Comparative  anatomy. 
Zygoma.  —  An  arch  or  yoke. 
Zygoinatic.  —  Belonging  to  the  zygoma. 


25 


EXPLANATION   OF   FIGURE   XIX. 


OSSEOUS  STRUCTURE. 


1. 

Frontalis. 

% 

Parietalis. 

3. 

Occipital. 

5. 

Nasal. 

6. 

Lachmyral. 

8. 

Superior  maxillaris. 

9. 

Aaterior        " 

10. 

Inferior  or  lower  jaw. 

u. 

Cervical  vertebrae. 

16. 

True  rib^ 

17. 

False  ribs. 

18. 

Sternum. 

19. 

Ileum. 

22. 

Femur. 

23'. 

Patella. 

24. 

Tibia. 

25. 

Os  calcis. 

26. 

Astragalus. 

21- 

Tarsal  bones. 

28. 

Metatarsus  njagnum. 

29. 

Sessamoids. 

30. 

Os  suflEi-aginis. 

31. 

Os  corona. 

32. 

Os  pecL's. 

33. 

Scapula. 

34. 

Qs  humeri. 

35. 

Radius. 

36; 

Carpus. 

37. 

INIetacarpus  magnum. 

39. 

Os  suffraginis. 

40. 

Os  corona. 

41. 

Os  pedis. 

MUSCULAR   STRUCTURE. 

FORWARD  PARTS.  —  THE  HEAD. 


a. 

Orbicularis  palpebrarum. 

6. 

Levator  palpebrae. 

c. 

Dilator  naris  lateralis. 

d. 

"           "      anterior. 

e. 

Orbicularis  oris. 

y. 

Nasalis  longus. 

S'. 

Levator  labii  superiorus. 

t. 

Buccinator, 

J. 

Retractor  labii  inferiorus. 

7c, 

Masscter. 

m. 

Attolentes  et  abducetis  a\irem. 

2, 

Facial  vein. 

THE  NECK. 

c". 

Trachelo  subscapularis.  —  Scaloiurf. 

6. 

Rhomboideus  longus. 

EXPLANATION    OF    FIGURE    XIX.    CONTINUKD. 

f.    Splemus. 

o.     Abducens  vel  dcprimcns  aurem. 

r.  t.  Tendon  ol'  ihc  splcnius  and  complcxus  major. 

V.     Stcnio  maxillaris, 

X.     Subscapulo  hyoideus. 

XHE  SIIOULDEK,  ANTERIOR  MUSCLES,  AND  FORE  EXTREMITIES. 

a.     Trapezius. 

6'.    Teres. 

c".    Pectoralis  pai-vus. 

f.    Antea  spiuatus. 

g".  Postea  spinatus. 

V\  r.  Triceps  extensor  brachii. 

o".  Pectoralis  transversalis. 

r".   Flexor  metacarpi  internus. 

s".  s".  Extensor  metacarpi  magnus. 

/.  f.  Extensor  metacarjii  obliquus. 

u.     Tendons  perforatus  and  perforans. 

u.     (At  the  luimeral  region.)     Levator  humeri. 

x".  x".  Extensor  tendons. 

8.     The  hoof. 

THE  ABDOMEN  AND   POSTERIOR  PARTS.  —  ABDOMINAL   REGION,   AND   OF  THE   COSTA. 

a".  Serratus  lumborum. 

o".  Obliquus  externus  abdominis  —  (beneath  the  dotted  hue). 

D.    Serratus  magnus. 

POSTERIOR   PARTS. 

g".  Ligaments  of  the  patella. 

h.  d.  e.  Glutei. 

A".     Extensor  metatarsi  internus. 

m.   Tensor  vagina. 

m".  Rectus. 

o".  Vastus  externus. 

u.     Gastrocnemius  internus. 

V.  V.  Flexor  pedis. 

u.     Flexors  jjerforatus  and  perforans. 

x".  x".  Fleshy  belly  of  the  extensor. 

X.  X.  Extensor  tendons. 

8.     The  hoof. 


fderinarg  Cfldc^kgkal  €\Mt 


(195) 


A  VETERINARY  TOXICOLOGICAL  CHART, 

CONTAINING    THOSE    AGENTS    AVHICH    ARE    KNOWN     TO    CAUSE     DEATH     IN     THE    HORSE  ; 
WITH    THE    SYMPTOMS,  ANTIDOTES,    ACTION    ON    THE    TISSUES,  AND  TESTS. 

BY  W.  J.  T.  MORTON, 

Lecturer  on  V^derinary ,  Materia  Medica,  etc. 

"  Poisons  are  substances  which  are  capable  of  altering  or  destroying,  in  a  majority  of 
cases,  some  or  all  of  the  functions  necessary  to  the  support  of  the  vital  principle."  — 
Faedere.  They  are  derived  both  from  the  organic  and  inorganic  kingdoms ;  and  their 
action  is  either  local  or  remote.  Local  action  is  referrable  to,  1st,  Chemical  Decomposi- 
tion ;  2d,  Irritation  and  Inflammation ;  3d,  Nervous  Impression.  Remote  action  is 
effected  by,  1st,  Absorption  ;  2d,  Sympathy.  Animal  Poisons  rank  first  in  potency;  next 
to  these,  the  Mineral ;  and  lastly,  the  Vegetable.  Aerial  poisons  are,  perhaps,  the  most 
insidious. 

The  manner  in  which  poisons  are  introduced  into  the  System  varies.  The  Alimen- 
tary Tube,  the  Skin,  the  Circulation,  and  the  Lungs,  are  the  media.  1st,  They  may  be 
taken  into  the  Stomach  inadvertently  with  the  food,  or  they  may  be  maliciously  or  acci- 
dentally administered.  They  may  also  be  thrown  up  as  Enemata.  2d,  They  may  be 
placed  underneath  the  Sldn  ;  or  injected  into  the  Circulation  ;  or  they  may  be  absorbed 
from  Wounds.  3d,  If  gaseous,  they  may  be  inhaled,  and  enter  the  blood  during  its 
transit  through  the  Lungs.  They  are  generally  arranged  according  to  the  effects  which 
they  produce  upon  the  Animal  Economy.  The  great  end  of  Toxicological  Science  is 
to  counteract  their  influence,  which  may  be  accomplished  by  chemically  decomposing 
them,  by  their  expulsion  from  the  System,  and  by  restoring  the  Function  of  the  Organ 
of  which  they  have  caused  derangement.  As  comparatively  large  quantities  of  the 
Poisons  are  required  to  destroy  Life  in  the  Horse,  the  niceties  of  chemical  manipulation 
in  the  application  of  Tests  are  uncalled  for.  It  will  generally  be  sufficient  to  collect 
some  of  the  contents  of  the  Stomach  and  Intestines,  add  distilled  Water  to  them,  filter  and 
to  the  Solution  apply  the  Test  or  Re-agent.  Sometimes  they  require  the  influence  of 
heat ;  and,  when  the  contents  are  not  attainable,  portions  of  the  Alimentary  Tube  which 
have  been  most  acted  upon  by  the  Agent  are  to  be  boiled  in  distilled  Water,  and  similarly 
treated. 


I.  — IRRITANT   POISONS. 

Tliese  produce  their  action  upon  some  part  of  the  Alimentary  Canal,  particularly  the  Stom- 
ach and  Intestines ;  and  by  absorption  they  are  often  carried  to  other  Organs.  The 
principal  Symptoms  are  those  of  Irritation  and  Inflammation. 


AGENTS. 

ACIDUM   SULPHURICUM. 

Sulphuric  Acid. 

ACIDUM    NITRICUM. 

Nitric  Acid. 

ACIDUM    HYDROCHLORICUM. 

Hydrochloric  Acid. 
Symptoms.  —  The  liquid   mineral    acids 


are  the  most  powerful  of  all  local  irritants. 
Indications  of  their  action  are  uneasiness, 
frequent  pawing  and  shifting  of  the  posi- 
tion, increased  secretion  of  saliva,  which  is 
sometimes  viscid  and  fetid,  the  mouth  in- 
flamed, difficulty  in  swallowing  from  corro- 
sion of  the  lining  of  the  esophagus,  acute 
gastric  irritation  extending  to  the  intestines, 
and  giving  rise  to  symptoms  resembling  a 

(197) 


198 


TOXICOLOGICAL  CHART. 


most  violent  attack  of  colic ;  pain  on  pres- 
sure being  applied  over  the  abdomen  ;  fre- 
quent attempts  to  dung  and  stale ;  and,  after 
the  faeces  have  been  voided,  a  discharge  of 
mucus  streaked  with  blood  takes  place : 
tenesmus,  pulse  quick  and  feeble,  prostra- 
tion of  strength,  profuse  perspiration,  cold- 
ness of  the  body,  and  death,  after  the  ani- 
mal has  endured  excruciating  agonies. 

Li  one  case  related  to  me,  nitric  acid  was 
poured  into  the  ear,  and  death  took  place 
from  inflammation  extending  to  the  mem- 
branes of  the  brain. 

Treatment.  —  As  the  general  symptoms 
of  poisoning  by  the  liquid  mineral  acids  do 
not  materially  differ,  neither  will  the  general 
treatment.  This  will  consist,  1st,  In  dilut- 
ing the  agent  by  throwing  into  the  stom- 
ach large  quantities  of  water  by  means  of 
Read's  pump.  2d,  In  neutralizing  it,  by 
suspending  in  the  water  chalk,  magnesia,  or 
soap ;  or,  in  the  absence  of  these,  the  plaster 
from  the  walls.  3d,  In  allaying  the  su- 
pervening inflammation  by  means  of  blood- 
letting, should  the  urgency  of  the  symp- 
toms demand  it ;  and  also  by  the  adminis- 
tration of  opium,  and  a  free  use  of  demul- 
cents. The  subsequent  nervous  debility 
and  prostration  of  strength  are  to  be  com- 
batted  by  the  milder  vegetable  tonics,  and 
a  gradual  return  to  liberal  diet. 

Morbid  Appearances.  —  The  mouth,  pha- 
rynx, and  esophagus,  present  traces  of  the 
action  of  the  peculiar  acid.  The  stomach 
is  distended  with  gas,  and  occasionally 
lined  with  its  disorganized  tissue,  which  is 
eroded  in  patches,  and  so  deeply  ulcerated 
as  to  form  perforations.  Intense  inflam- 
mation often  exists  in  this  viscus,  which 
extends  throughout  the  whole  of  the  intes- 
tinal tube,  involving  its  peritoneal  tunic; 
this  last  circumstance  has  been  thought  to 
be  distinctive  between  poisoning  by  acids 
and  metallic  compounds  ;  this  cannot,  how- 
ever, be  relied  upon.  The  blood  in  the 
larger  vessels  sometimes  forms  a  firm  clot. 
These  appearances  will  not  be  so  marked 
when  an  acid  has  been  given  in  small  doses 
for  some  time,  or  if  much  diluted  we  may 


then  expect  to  find  the  coats  of  the  stom- 
ach and  intestines  thickened  and  contracted, 
the  result  of  chronic  inflammation,  with 
here  and  there  eroded  spots,  but  not  of  any 
depth. 

Tests.  —  General.  —  Sour  taste  —  neu- 
tralization by  the  alkalies  —  effervescing 
with  the  carbonates  —  reddening  of  litmus 
paper. 

Particular. —  Sulphuric  Acid. — The  parts 
with  which  it  comes  in  contact  are  first 
whitened,  and  then  changed  to  a  brownish 
color.  By  macerating  them  or  the  con- 
tents of  the  stomach  in  distilled  water,  fil- 
tering, and  adding  a  solution  of  the  nitrate 
of  barptes,  an  insoluble  precipitate,  the  sul- 
phate of  bari/tes,  is  obtained. 

Nitric  Acid.  —  The  tissues  changed  of  a 
yellow  color,  which  is  heightened  by  am- 
monia. The  filtered  solution  boiled  on 
copper  flings  in  a  test  tube  emits  orange- 
colored  fumes  of  nitrous  acid.  Potassa  be- 
ing added  to  it,  by  evaporation  a  salt  is  ob- 
tained, wiiich  deflagrates ;  or  a  piece  of 
bibulous  paper  may  be  saturated  with  the 
solution,  dried,  and  inflamed. 

Hydrochloric  Acid.  —  Tissues  blanched. 
Its  fumes  are  rendered  more  manifest  by  a 
rod  dipped  in  ammonia  being  held  in  them. 
This  test,  however,  we  are  rarely  able  to 
avail  ourselves  of.  On  the  addition  of 
nitrate  of  silver  to  the  solution,  it  gives  a 
white  precipitate,  the  chloride  of  silver. 

AGENT. 

ACIDUM    OXALICUM. 

Oxalic  Acid. 

Bymptoms.  —  Instances  are  recorded  of 
horses  having  been  poisoned  by  this  acid, 
but  whether  maliciously  given,  or  adminis- 
tered by  mistake  for  the  sulphate  of  mag- 
nesia, I  cannot  say.  The  symptoms  atten- 
dant on  its  action,  when  a  concentrated 
solution  is  given,  will  not  be  dissimilar  to 
those  produced  by  the  mineral  acids.  When 
diluted,  however,  it  is  said  to  cause  death 
by  palsying  the  heart  and  nervous  system, 
or  by  inducing  tetanus  or  narcotism ;  but  I 


TOXICOLOGICAL   CHART. 


199 


am  not  aware  that  such  action  has  been  ob- 
served in  the  horse. 

Treatment.  —  Avoid  large  quantities  of 
water,  as  it  favors  the  absorption  of  the 
acid.  Throw  into  the  stomach  a  mixture 
of  chalk,  or  of  magnesia  and  water,  partic- 
ularly the  former ;  or  lime  from  the  walls 
may  be  used ;  either  of  which  will  form  an 
insoluble  salt.  The  alkalies  are  inadmissi- 
ble, because  they  form  soluble  salts.  De- 
mulcents to  be  freely  employed,  and  the 
remaining  irritation  to  be  allayed  by  opium. 

Morbid  Appearances.  —  None  recorded 
in  the  horse.  In  other  animals  the  stom- 
ach has  been  found  to  contain  black  extra- 
vasated  blood,  its  inner  coat  being  of  a 
cherry -red  color;  in  some  places  the  sur- 
face is  brittle,  and  the  subjacent  stratum 
gelatinized.  The  intestines  are  usually  in- 
flamed throughout.  When  its  influence 
has  been  through  the  medium  of  the  blood 
on  remote  parts,  the  heart  has  been  found 
to  have  lost  its  contractility,  and  to  contain 
arterial  blood. 

Tests.  —  Acid  reaction  on  litmus  paper. 
A  concentrated  solution  with  ammonia 
forms  a  salt  whose  crystals  radiate,  the  ox- 
alate of  ammonia. 

Hydro  chlorate  of  Lime  throws  down  a 
white  precipitate  which  is  soluble  in  nitric 
acid,  the  oxalate  of  lime. 

Sulphate  of  Copper  yields  a  blue  or  green- 
ish-white precipitate,  the  oxalate  of  copper. 

Nitrate  of  Silver  causes  a  dense  white 
precipitate  ;  also  an  oxalate  which,  when 
dried  and  heated,  fulminates. 

.      AGENT. 

ACIDUM    ARSENIOSUM. 

Arsenious  Acid, 
White  Arsenic. 

Symptoms.  —  Intense  pain,  resembling 
acute  enteritis;  belly  tympanitic,  with  a 
rumbling  noise  in  the  intestines ;  the  dejec- 
tions offensive,  and  mixed  with  mucus ; 
pulse  quick  and  feeble,  becoming  scarcely 
perceptible  at  the  jaw ;  respiration  labori- 
ous; surface  of  the  body  covered  with  an 
extremely  cold,  clammy  sweat ;  extremities 


cold;  efforts  to  vomit;  countenance  anx- 
ious, and  indicative  of  great  torture ;  mu- 
cous tissues  injected  ;  mouth  hot ;  increased 
secretion  of  saliva,  which  is  singularly  fetid ; 
delirium  from  pain  which  has  become  con- 
tinuous; exhaustion;  death.  The  action 
of  this  poison  is  not  merely  as  a  local  irri- 
tant, it  being  often  conveyed  to  remote 
parts  through  the  medium  of  the  circula- 
tion, thus  causing  death.  Even  as  an 
external  applicant  it  has  been  known  to  pro- 
duce much  general  derangement  of  the  sys- 
tem, independent  of  its  influence  as  an 
escharotic,  which  is  powerful.  On  this 
account,  when  the  methods  usually  resorted 
to  have  failed  to  demonstrate  its  existence 
in  the  contents  of  the  stomach  and  intes- 
tines, Orfila  has  succeeded  in  detecting  it 
in  the  organic  tissues,  particularly  the  liver. 
Treatment.  —  A  free  use  of  diluents,  or 
of  lime  water ;  avoid  blood-letting,  as  this 
promotes  the  absorption  of  the  poison ; 
give  large  doses  of  the  hydrated  peroxide 
of  iron  precipitated  by  ammonia  from  a 
solution  of  the  sulphate  of  iron,  so  as  to 
forin  an  insoluble  arsenic  of  iron,  which 
may  be  expelled  by  the  action  of  active 
purgatives.  The  subsequent  inflammation 
is  to  be  combatted  by  the  ordinary  antiphlo- 
gistic remedies ;  while  the  debility  which 
supervenes,  and  which  is  often  great,  is  best 
counteracted  by  the  vegetable  tonics  and 
judicious  dieting. 

Morbid  Appearances.  —  The  stomach  and 
intestines,  especially  the  latter,  highly  in- 
flamed and  ulcerated  in  patches.  The 
cEecum  and  colon  present  the  most  marked 
action,  the  villous  coat  being  black  from  an 
effusion  of  altered  blood,  and  the  peritoneal 
tunic  involved.  Congestion  of  blood  in  the 
lungs,  liver,  and  kidneys ;  redness  of  the 
lining  membrane  of  the  windpipe,  extend- 
ing to  the  air-passages  generally  ;  conjunc- 
tival membrane  highly  injected,  and  the 
blood  in  a  fluid  state  throughout  the  body. 
Ecchymosis  in  the  heart. 

Tests.  —  1st,  by  Reduction.  —  The  sus- 
pected powder,  being  dried,  is  to  be  mixed 
with  twice  its  weight  of  newly-burnt  and 
pulverized  charcoal,  and  introduced  into  a 


200 


TOXICOLOGICAL   CHART. 


test-tube :  the  heat  of  a  spirit  lamp  is  now 
to  be  applied ;  first  to  the  upper  part  of  the 
mixture,  and  afterwards  steadily  to  the  bot- 
tom of  the  tube,  when,  if  arsenious  acid  is 
present,  the  metal  arsenicum  will  be  sub- 
limed, and,  encoating  the  tube,  form  a  ring 
of  a  polished-steel  lustre,  the  inner  surface 
of  which  is  crystalline.  The  little  watery 
vapor,  which  will  be  condensed  within  the 
tube  before  the  metallic  crust  begins  to  ap- 
pear,* is  to  be  removed  by  a  roll  of  bibulous 
paper. 

2c?,  by  Liquid  Re-agents.  —  The  contents 
of  the  stomach,  or  such  parts  of  that  viscvis 
as  have  been  acted  upon,  being  boiled  in 
distilled  water,  the  solution  is  to  be  filtered. 
The  ammoniacal  sulphate  of  copper  added  to 
this  gives  an  apple-green  precipitate,  the  ar- 
senite  of  copper.  The  ammoniacahiitrate  of 
silver,  a  lemon-yellow  precipitate,  changing 
to  a  dark  brown  on  exposure  to  light,  the 
arsenite  of  silver.  Sulphuretted  Hydrogen, 
—  generated  by  the  action  of  dilute  suphu- 
ric  acid  on  suphuret  of  iron,  in  a  flask,  hav- 
ing an  emerging  tube  bent  at  a  double  right 
angle,  —  passed  up  through  the  solution  for 
ten  or  fifteen  minutes,  gives  a  sulphur  yel- 
low precipitate,  the  sulphuret  of  arsenicum. 
Water  impregnated  wdth  this  gas  affords 
the  like  compound.  The  solution  for  this 
test  must  be  perfectly  neutral.  This  pre- 
cipitate may  be  afterwards  subjected  to  re- 
duction. 

Zd,  by  Nascent  Hydrogen. —  This  is  ef- 
fected in  Marsh's  tube.  The  fluid  con- 
tents of  the  stomach,  or  the  filtered  solution 
before  spoken  of,  being  introduced  into  it, 
zinc  and  sulphuric  acid  are  added,  and  the 
arseniuretted  hydrogen  as  it  escapes  from 
the  jet  inflamed,  when  ivater  and  metallic 
arsenic  will  be  condensed  upon  the  glass 
disc  held  above  it.  The  former  will  be  dis- 
sipated by  the  heat,  and  around  the  latter 
a  ring  of  arsenious  acid  may  be  seen.  In 
the  absence  of  a  Marsh's  tube,  a  common 
two-ounce  wide-mouthed  vial,  with  a  cork 
perforated  by  a  piece  of  glass  tube  or  even 
tobacco-pipe,  may  with  care  be  made  to  an- 
swer all  the  purpose. 


AGENT. 

HYDRARGVRI    BICHLORIDUM. 

Bichloride  of  Mercury, 
Corrosive   Sublimate. 

Symptoms. —  The  effects  which  follow 
the  administration  of  large  doses  of  this 
salt,  resemble  those  which  supervene  when 
the  mineral  acids  have  been  given,  except 
that,  generally,  super-purgation  is  present, 
and  the  foecal  matter  is  profuse  and  highly 
offensive.  Its  solubility  renders  it  more 
energetic  than  arsenious  acid,  although  it  is 
not  so  frequently  had  recourse  to  for  poi- 
soning. 

The  protochloride  of  mercury,  calomel, 
when  incautiously  given,  has  also  caused 
death,  by  inducing  inflammation  of  the  mu- 
cous lining  of  the  intestines,  accompanied 
with  violent  purging  and  tenesmus. 

Treatment.  —  The  white  of  eggs  suspend- 
ed in  water,  the  albumen  of  which  renders 
the  bichloride  of  mercury  insoluble  ;  or  large 
quantities  of  wheat-flour,  or  milk.  Iron 
filings  have  also  been  advocated,  which, 
reviving  the  metallic  mercury,  may  be  ex- 
pelled by  purgatives  ;  a  free  use  of  dilutents. 
The  treatment  of  the  salivation,  which 
sometimes  supervenes,  consists  in  exposure 
to  cool  air,  the  exhibition  of  saline  purga- 
tives, and  nourishing  diet. 

Morbid  Appearances.  —  These  would 
closely  resemble  the  effects  produced  by  the 
above  agent,  the  mucous  lining  of  the  ali- 
mentary canal  being  intensely  inflamed 
throughout,  its  texture  destroyed,  and  in 
parts  corroded.  The  disorganized  tissue 
often  contains  the  poison,  which  it  yields 
by  analysis. 

Tests.  —  Lime-icater,  which  throws  down 
an  orange  yellow  precipitate,  the  hyd rated 
binoxide  of  mercury. 

Iodide  of  Potassium,  which  gives  a  beau- 
tiful scarlet  compound,  the  biniodide  of 
mercury. 

Protochloride  of  Tin,  which  first  aflbrds 
a  whitish  precipitate,  the  protochloride  of 
mercury ;  and,  on  adding  more  of  the  test 
a   grayish-black    powder   is  formed,  wliich 


TOXICOLOGICAL   CHAET. 


201 


consists  of  minutely  divided  metallic  mer- 
cury. 

Sulphuretted  Hydrogen,  which  gives  a 
blackish  compound,  a  sulphuret  of  mercury. 

To  these  may  be  added  the  test  hy  re- 
duction, the  reducing  agent  being  the  pro- 
tochloride  of  tin,  assisted  by  heat. 

Albumen  is  not  now  relied  on  as  a  re- 
agent. 

AGENT. 

ANTIMONII    POTASSIO-TARTRAS. 

Potassio- Tartrate  of  Antimany, 
Emetic  Tartar. 

Symptoms.  —  Violent  gastric  irritation ; 
nausea ;  efforts  to  vomit ;  profuse  perspira- 
tion; catharsis,  accompanied  with  colicky 
pains  and  much  flatus  ;  increased  secretion 
of  urine ;  the  heart's  action  at  first  much 
quickened,  and  afterwards  scarcely  percep- 
tible ;  labored  resph'ation ;  injection  of  the 
mucous  tissues  ;  extreme  distress  ;  death. 
.  Treatment.  —  The  yellow  bark,  or  any 
other  astringent  vegetable  that  contains 
tannin,  to  be  administered  both  in  powder 
and  decoction  ;  a  free  use  of  dilutents,  olea- 
ginous purges,  and  opium,  should  then  be 
had  recourse  to  for  the  purpose  of  allaying 
the  irritation. 

Morbid  Appearances.  —  The  stomach 
highly  inflamed,  and  eroded  patches  on  the 
mucous  coat,  which  are  of  a  deeper  color 
than  the  surrounding  parts  ;  intestines  red- 
dened, encoated  mth  slimy  mucus,  and 
thickened ;  lungs  gorged  with  blood ;  and 
general  inflammation  of  the  whole  system 
consequent  on  its  absorption. 

Tests.  —  Caustic  Potass  and  Lime-ivater, 
which  precipitates  the  oxide  of  antimony' 
The  carbonate  of  potass  acts  with  still 
greater  delicacy. 

Hydrochloric  and  Sulphuric  Acids  also 
afford  the  like  precipitate.  A  strong  infu- 
sion of  the  gall-nut  gives  a  dirty,  yellowish 
white  precipitate,  the  gallate  of  antimony. 

Sulphuretted  Hydrogen  throws  down  an 
orange-red  precipitate,  the  red  sulphuret  of 
antimony,  which  is  so  peculiar  as  to  be  al- 
ways distinguished ;  and  the  reduction  of 


this  precipitate  by  hydrogen  at  once  dissi- 
pates all  doubt. 

AGENT. 

SALTS  OF  COPPER. 

Symptoms.  —  The  salts  of  copper  are 
rarely  employed  as  poisons  to  the  horse. 
Large  doses  of  the  sulphate  improperly 
given  have  sometimes  caused  much  intes- 
tinal irritation,  followed  by  colicky  pains 
and  diarrhoea ;  and,  in  one  instance,  death 
from  gastro-enteritis.  Doubtless  inordinate 
quantities  would  always  destroy  life,  when 
symptoms  similar  to  those  caused  by  any 
other  erodent  would  be  manifested,  it  being 
a  local  irritant.  The  same,  perhaps,  may 
be  said  of  the  impure  acetate  of  copper. 

In  the  neighborhood  of  works  for  smelt- 
ing of  copper,  horses  are  frequently  attacked 
with  diseases  of  the  joints,  indicated  by 
swelling,  bursal  distension,  exostosis,  and, 
ultimately,  anchylosis,  arising  either  from 
the  state  of  the  herbage  or  the  impregnation 
of  the  air  by  the  vapors  disengaged. 

Treatment.  —  Give  a  solution  of  the  fer- 
rocyanide  of  potassium,  or  of  soap.  Albu- 
men is  also  an  antidote,  and  metallic  iron, 
which  latter  precipitates  the  copper.  This 
is  to  be  expelled  by  oleaginous  purgatives. 
Tepid  water  rendered  slightly  alkaline  may 
also  be  freely  given;  and  opium,  to  allay 
u'ritation.  A  free  use  of  demulcents,  as 
gruel,  infusion  of  linseed,  etc.,  is  indicated. 

For  the  local  affection,  puncture  the  bur- 
sal distention,  and,  after  the  evacuation  of 
the  cyst,  apply  an  elastic  bandage,  giving 
gentle  compression.  Remove  the  animal 
to  another  locality. 

Morbid  Appearances.  —  Stomach  ulcer- 
ated where  the  agent  has  adhered,  and  gen- 
eral inflammation  of  its  mucous  lining 
and  that  of  the  intestines,  with  here  and 
there  spots  of  erosion.  In  the  instance  ad- 
verted to  of  the  sulphate  of  copper  causing 
death,  there  was  an  engorgement  of  the 
blood-vessels  of  the  lungs. 

Copper  is  with  extreme  difficulty  detected 
in  any  of  the  secretions.  It,  however,  has 
been  found  in  the  organic  tissues,  particu- 


202 


TOXICOLOGICAL   CHART. 


larly  the  liver  after  incineration,  and  also  in 
the  blood. 

Tests.  —  Water  of  Ammonia  affords  an 
azure-colored  precipitate,  or  a  violet-colored 
solution,  the  ammoniuret  of  copper. 

Ferrocyanide  of  Potassium  causes  a 
brown  precipitate,  the  ferrocyanide  of  cop- 
per. 

Sulphuretted  Hydrogen  throws  down  a 
blacldsh  compound,  the  sidphuret  of  copper. 

A  piece  of  polished  iron  introduced  into 
the  solution  is  soon  covered  with  metallic 
copper. 

AGENT. 

SALTS    OF    LEAD. 

Symptoms.  —  Of  these,  like  the  above, 
comparatively  large  quantities  are  required 
to  cause  death.  Violent  spasms,  tremors, 
obstinate  constipation  of  the  bowels,  fol- 
lowed by  paralysis,  partial  or  complete,  are 
the  usual  indications. 

In  the  neighborhood  of  lead  works  ani- 
mals are  often  thus  affected,  when,  in  addi- 
tion to  these  symptoms,  there  is  a  depraved 
appetite  present:  the  stomach  after  death 
being  found  filled  to  repletion  with  strange 
and  incongruous  substances. 

Treatment.  —  Solutions  of  the  sulphate 
of  magnesia  or  soda,  combined  with  croton 
or  linseed  oil ;  afterwards  allaying  the  irri- 
tation by  means  of  opium. 

The  phosphate  of  soda  has  also  been  ex- 
tolled as  an  antidote. 

The  treatment  for  the  paralysis  which 
remains  consists  in  judicious  dieting  and 
exercise. 

Morbid  Appearances. —  The  lining  mem- 
brane of  the  stomach  and  intestines  is 
sometimes  inflamed,  sometimes  blanched; 
the  caliber  of  the  latter  is  diminished,  and 
its  coats  coiTUgated  ;  the  muscular  tissue 
throughout  the  body  has  lost  its  power  of 
contractility  ;  the  buccal  membrane  is  pale, 
and  the  blood  of  a  brighter  color  than  nat- 
ural. 

Tests. —  Chromate  of  Potass  throws  down 
a  yellow  precipitate,  the  chromate  of  lead. 


Iodide  of  Potassium  likewise  gives  a  yel- 
low precipitate,  tlte  iodide  of  lead. 

Sulphuretted  Hydrogen  causes  a  black 
precipitate,  the  stilphuret  of  lead. 

A  rod  of  Zinc  introduced  into  it  causes 
a  deposition  of  metallic  lead  in  a  crystalline 
form. 

The  alkaline  carbonates  and  sulphates, 
although  they  give  white  precipitates  with 
lead,  have  been  objected  to  as  tests. 

AGENT. 

POTASSJE    NITRAS. 

Nitrate  of  Potash, 
Nitre. 

Symptoms. —  Much  uneasiness ;  cholicky 
pains ;  pulse  feeble,  quick,  and  irregular ; 
respiration  accelerated;  mouth  hot;  mu- 
cous lining  of  the  eyelids  and  nostrils 
highly  injected ;  increased  secretion  of 
urine ;  frequent  voiding  of  faeces.  If  the 
quantity  given  is  very  great,  the  abdominal 
pains  are  more  intense ;  the  breathing  more 
labored;  the  pulse  quicker;  ineffectual  ef- 
forts to  stale  are  made  ;  the  extremities  are 
cold ;  and  the  prostration  of  strength  is 
extreme.  If  not,  after  manifesting  much 
uneasiness,  the  faeces  are  frequently  voided ; 
diuresis  supervenes  ;  and  relief  is  obtained. 

Treatment.  —  A  free  use  of  demulcents; 
oleaginous  purgatives ;  hot  rugs  to  the  ab- 
domen, and  over  the  loins  ;  opiate  enemata ; 
if  necessary,  the  abstraction  of  blood ;  with 
hand-rubbing,  and  bandages  to  the  extremi- 
ties. Possibly  a  mustard  cataplasm  or  a 
sheepskin  over  the  loins  will  be  of  service. 
Such  counter  irritants  as  are  likely  to  be 
carried  to  the  kidneys  are  to  be  avoided. 

Morbid  Appearances.  —  The  villous  coat 
of  the  stomach  highly  inflamed  and  studded 
with  dark  spots  resembling  ecchymosis, 
varying  in  size  and  running  into  patches ; 
they  are  easily  scraped  off,  and  contain  a 
deposit  of  serum.  The  cuticular  coat  is 
also  inflamed,  but  not  so  highly,  and  its 
texture  is  much  weakened ;  the  small  intes- 
tines are  pervaded  with  an  inflammatory 


TOXICOLOGICAL   CHART. 


203 


blush ;  the  lungs  and  heart  are  congested, 
and  the  venous  blood  is  of  a  brighter  color 
than  usual.  Constriction  and  inflamma- 
tion of  the  neck  of  the  bladder  have  also 
been  observed. 

Tests.  —  From  the  fluid  contents  of  the 
alimentary  tube,  or  from  the  urine,  the  salt 
may  be  obtained  by  evaporation  and  crystal- 
lization. It  is  known  by  deflagrating  when 
thrown  on  a  piece  of  ignited  charcoal,  of 
which  it  animates  the  combustion ;  and  by 
yielding  nitric  acid  when  distilled  with  sul- 
phuric acid.  Heat  also  disengages  oxygen 
from  it. 

Chloride  of  Platinum  added  to  its  solu- 
tion gives  a  yellow  precipitate. 

AGENT. 

CANTHARIS. 

''  77ie  Blistering  Fly. 

Symptoms.  —  Much  uneasiness  ;  intesti- 
nal irritation ;  frequent  attempts  to  stale ; 
strangury ;  bloody  urine  ;  accelerated  pulse 
and  respiration  ;  continual  pain,  with  much 
constitutional  disturbance.  These  symp- 
toms increase  in  urgency,  until  death  closes 
the  scene. 

Treatment.  —  Expulsion  of  the  agent 
from  out  of  the  alimentary  tube  by  brisk 
purgatives ;  oil  is  objectionable,  on  account 
of  the  solubity  of  the  active  principle  of 
the  cantharides  in  it.  A  free  use  of  dilu- 
ents ;  opium  may  be  given,  and  oleaginous 
and  demulcent  injections  thrown  into  the 
bladder.  Sheepskins  over  the  loins ;  hot 
rags  over  the  abdomen. 

Morbid  Appearances.  —  The  mucous  lin- 
ing of  the  alimentary  canal  throughout  in 
a  high  state  of  diffused  inflammation  ;  but 
the  urinary  organs  are  principally  affected : 
the  blood-vessels  of  the  kidneys,  bladder, 
and  urethra,  are  much  engorged,  and  the 


lining  membrane  of  the  latter  has  in  some 
places  a  sphaceletic  appearance. 

Tests.  —  Washing  of  the  contents  of  the 
stomach  and  alimentary  tube  will  develop 
portions  of  the  beautiful  green  case-wings 
of  the  fly,  which  appear  not  quickly  to  un- 
dergo decomposition ;  Orfila  having  detected 
them  in  a  body  some  months  after  death. 

AGENTS. 

BITE    OF    THE    VIPER, 

STING    OF    THE    HORNET,  WASP,  ETC. 

Symptoms.  —  Subcutaneous  inflamma- 
tion, indicated  by  swelling  and  increased 
heat,  with  effusion  into  the  cellular  tissue, 
which  sometimes  goes  on  to  gangrene; 
pain  ;  constitutional  excitement ;  quickened 
and  irregular  pulse  ;  rigors. 

The  bite  of  a  viper  has  been  known  to 
cause  cerebral  derangement  and  death,  by 
its  influence  on  the  nervous  system. 

Treatment.  —  Removal  of  the  stings ; 
counter-irritants,  as  liniment  of  ammonia 
or  turpentine,  which,  if  sufficient,  are  to  be 
followed  by  scarification,  the  use  of  emol- 
lients, and  the  general  antiphlogistic  reme- 
dies, such  as  bleeding,  fomentations,  and 
laxatives,  with  opium  to  allay  the  general 
irritation.  The  virus  of  the  tooth  of  the 
viper  may  be  extracted  by  cupping,  or, 
which  is  preferable,  let  the  part  be  excised, 
and  the  nitrate  of  silver  freely  applied 
afterwards. 

Morbid  Appearances.  —  But  few  instances 
of  death  are  recorded.  If  it  takes  place,  it 
is  probably  the  result  of  sympathetic  and 
general  excitement  of  the  whole  system; 
the  usual  indications,  therefore,  of  increased 
nervous  and  vascular  action  may  be  ex- 
pected to  be  met  with. 

Tests.  —  None. 


204 


TOXICOLOGICAL    CHART 


IL  — NARCOTIC   POISONS. 


These  produce  Stupor,  Delirimn,  and  other  affections  of  (he  Brain  and  Nervous  Si/stem, 

followed  by  Death. 


AGENT. 

OPIUM. 

Ojnian. 

Symptoms.  —  The  horse  will  bear  large 
doses  of  this  drug ;  the  quantity  necessary 
to  destroy  life  is  consequently  great.  Sup- 
posed instances  are  recorded  of  its  causing 
death  when  given  in  doses  of  a  few  drachms 
in  order  to  check  superpurgation  ;  also  when 
the  animal  has  been  debilitated  by  disease, 
when  symptoms  of  enteritis  have  shown 
themselves,  accompanied  with  a  torpitude 
of  the  bowels,  and  much  suffering  previous 
to  death.  Much  larger  quantities  have, 
however,  often  been  given  with  impunity, 
and  frequently  "with  advantage. 

Treatment.  —  Expulsion  of  the  agent 
from  out  the  alimentary  tube  by  means  of 
oleaginous  purgatives,  enemata,  venesec- 
tion, and  a  free  use  of  demulcents,  with 
fomentations  to  the  abdomen,  and  counter- 
irritants  to  the  extremities. 

Should  a  state  of  stupor  prevail,  exercise 
may  be  given,  and  cold  water  dashed  over 
the  head. 

Morbid  Appearances.  —  The  mucous  lin- 
ing of  the  stomach  and  intestines  inflamed, 
and  easily  torn  asunder,  the  inflammation 
being  diffused.  This  has  been  thought  to 
be  a  distinctive  between  the  effects  induced 
by  mineral  and  vegetable  poisons ;  but  it 
cannot  be  relied  upon,  as  repeated  small 
doses  of  an  erodent  will  induce  the  like 
appearances,  only  there  will  be  more  thick- 
ening of  the  tunics. 

Tests.  —  Odor,  which  is  characteristic. 
To  the  suspected  matter  add  distilled  water 
acidulated  with  acetic  acid ;  agitate  for  a 
few  minutes,  filter  and  evaporate  to  the  con- 
sistence of  syrup  ;  boil  this  in  alcohol,  and 
again  filter  and  evaporate ;  dissolve  the  re- 
siduum in  distilled  water,  and  add  to  the 
solution  acetate  of  lead,  which  leaves  mor- 


phia in  solution :  this  being  heated  with 
sulphuretted  hydrogen,  any  remaining  lead 
will  be  precipitated.  On  nitric  acid  being 
added  to  the  morphia  obtained  by  evapora- 
tion, it  dissolves  with  effervescence,  and 
becomes  of  an  orange-red  color.  Suspended 
in  water  and  treated  with  a  drop  or  two  of 
the  permuriate  of  iron,  it  is  also  dissolved, 
and  forms  a  greenish-blue  solution. 

AGENT. 

TAXUS    BACCATA. 

The  Yeio. 

Symptoms.  —  Effects  variable ;  large  quan- 
tities have  sometimes  failed  to  cause  any 
injury,  while  at  others  comparatively  small 
quantities  have  destroyed  life.  It  would 
appear  to  be  very  insidious  in  its  influence, 
as  the  animal  generally  drops  down  dead 
without  indicating  any  previous  suffering. 
In  some  instances  slight  convulsions  have 
preceded  death.  The  partially  dried  leaves 
appear  to  be  more  energetic  than  the  green 
leaves,  probably  from  greater  quantities  be- 
ing partaken  of. 

Treatment. —  Usually  no  opportunity  is 
afforded  for  the  employment  of  remedies. 
Should  it,  however,  be  the  case  that  the 
leaves  of  yew  are  suspected  to  have  been 
eaten,  I  am  not  aware  of  any  method  which 
could  be  adopted  but  that  of  endeavoring 
to  expel  them  from  the  system  as  quicldy 
as  possible,  which  may  be  effected  by  active 
pm-gatives.  The  after-treatment  wall  de- 
pend upon  the  symptoms  which  may  pre- 
sent themselves. 

Morbid  Appearances.  —  The  alimentary 
tube  distended  with  faecal  matter  in  a  semi- 
fluid state,  and  highly  fetid  gases. 

The  mucous  lining  inflamed  throughout, 
particularly  of  the  larger  intestines,  with 
here  and  there  patches  of  extravasated 
blood. 


TOXICOLOGICAL   CHART. 


205 


In  some  few  cases  scarcely  a  trace  of 
diseased  action  in  the  tissues  could  be 
found. 

Tests.  —  Portions  of  the  vegetable  in  the 
stomach  and  intestines  mixed  with  the  in- 
gesta. 

The  active  principle  of  the  poison  is 
unknown,  hence  the  difficulty  in  the  treat- 
ment. 

AGENT. 

ACIDUM    HYDROCYANICUM. 

Hydrocyanic  Acid, 
Priissic  Acid. 

Symptoms.  —  Its  influence  is  sudden,  and 
that  of  a  powerful  sedative  to  the  system, 
and,  when  the  quantity  is  not  large,  evanes- 
cent: otherwise  it  is  followed  by  marked 
cerebral  derangement,  manifested  by  giddi- 
ness and  coma ;  the  breathing  becomes 
laborious  ;  the  nostrils  expanded ;  the  pulse 
quickened  and  fluttering ;  much  debility  is 
present,  with  loss  of  power :  to  these  suc- 
ceed tetanic  spasms  ;  the  muscles  become 
rigid  ;  the  jaws  locked,  and  the  membrana 
nictitans  is  forced  over  the  eye,  which  is 
prominent,  and  has  a  glassy  appearance ; 
profuse  perspiration  covers  the  body,  accom- 
panied by  violent  convulsions  and  intense 
suffering.  These  effects  are  succeeded  by 
a  remission  for  a  time,  during  wliich  the 
animal  appears  to  be  in  a  state  of  partial 
insensibility;  but  the  exacerbations  return 
again  and  again,  and  then  the  paroxysms 
become  less  and  less  powerful,  until  at 
length,  aU  action  disappearing,  the  animal 
is  left  in  a  state  of  exhaustion,  the  vital 
powers  being  much  depressed.  In  what- 
ever way  the  agent  is  introduced  into  the 
system,  the  effects  are  similar.  The  most 
active  form  of  the  poison  is  that  of  vapor. 

When  the  dose  is  sufficiently  large  to 
cause  death,  it  is  unaccompanied  with  suf- 
fering. 

Treatment.  —  Cold  affiisions  over  the 
body ;  the  inhalation  of  dilute  ammoniacal 
and  chlorine  gases,  particularly  the  latter. 

The  coma  may  be  removed  by  blood- 
letting;   and  diffusible  stimulants,  such  as 


ammonia,  may  be  administered,  combined 
with  tonics  to  rouse  the  depressed  vital 
powers. 

Of  course  this  treatment  will  only  be  of 
service  when  the  drug  has  been  too  fre- 
quently given,  or  administered  in  too  large 
quantities. 

Morbid  Appearances.  —  The  inner  tunic 
of  the  stomach  and  intestines  slightly  in- 
flamed; the  vessels  of  the  lungs  gorged 
with  blood;  the  parenchjnua  natural;  the 
lymphatics  containing  red  blood  ;  the  heart 
inflamed,  and  spots  of  ecchymosis  on  its 
lining  membrane ;  the  vessels  of  the  brain 
highly  injected,  particularly  those  of  the 
medullary  portion,  in  which  organ  the  odor 
of  the  acid  is  easily  recognized,  as  well  as 
throughout  the  body,  and  particularly  in  the 
halitus  from  the  blood.  The  eyes  are  glis- 
tening and  prominent. 

Tests.  —  Render  fluid  the  contents  of  the 
stomach,  and  distil  an  eighth  part  over,  when 
the  following  tests  will  be  available :  The 
odor,  which  resembles  that  of  bitter  al- 
monds, and  impresses  the  tlu'oat  and  nos- 
trils Mdth  a  peculiar  acridity. 

Sulphate  of  Copper,  the  solution  being 
rendered  alkaline  by  potass,  throws  down  a 
green  precipitate,  which  becomes  nearly 
white  on  adding  a  little  hydrochloric  acid, 
the  cyanide  of  copper. 

Sulphate  of  the  Protoxide  of  Iron,  simi- 
larly employed,  gives  a  greenish  precipitate, 
which  becomes  of  a  deep  blue  color  on  the 
addition  of  sulphuric  acid,  the  ferrocyanate 
of  the  protoxide  of  iron. 

Nitrate  of  Silver  throws  down  a  white 
precipitate,  the  cyanide  of  silver,  which  is 
soluble  in  nitric  acid  only  at  its  boiling 
temperature,  and  which,  when  dried  and 
heated  in  a  tube,  emits  cyanogen  gas,  which 
burns  with  a  rose-colored  flame. 

AGENT. 

CARBONIC     ACID. 

Symptoms.  —  Instances  are  known  of 
horses  having  been  suffocated  during  fires, 
arising  from  the  disengagement  of  this  gas, 
with,  perhaps,  some  of  the  compounds  of 


206 


TOXICOLOGICAL   CHART. 


hydrogen.  Its  sources  otherwise  are  abund- 
ant. In  a  state  of  dilution  it  causes  coma ; 
when  pure,  spasm  of  the  glottis,  and  death 
by  asphyxia. 

Treatment.  —  Removal  to  the  air  ;  cold 
affusions  over  the  body;  bloodletting;  dif- 
fusible stimulants. 

Morbid  Appearances.  —  Engorgement  of 
the  vessels  of  the  lungs  with  black  blood. 
The  v^^ssels  of  the  brain  and  of  the  heart 
are  in  a  similar  state.  The  bronchi  and 
trachea  filled  with  frothy  mucus. 

Tests.  —  The  tests  for  carbonic  acid  gas 
are  simple  enough,  but  here  they  are  inap- 
plicable. 

A  GENT. 

SULPHURETTED    HYDROGEN. 

Symptoms.  —  This  gas,  given  off  from 
cesspools  and  other  places,  has  been  at 
times  the  cause  of  death.     It  is  rapidly  ab- 


sorbed by  the  blood,  and  produces  coma 
and  tetanic  convulsions.  Sometimes  death 
takes  place  from  asphyxia. 

Treatment.  —  The  same  as  the  above  ; 
to  which,  perhaps,  may  be  added  the  inha- 
lation of  dilute  chlorine. 

Morbid  Appearances.  —  The  muscles  have 
lost  their  power  of  contractility.  The 
blood-vessels  are  gorged  with  fluid  black 
blood;  the  bronchial  tubes  inflamed,  with 
increased  secretion  of  mucus  both  in  them 
and  the  trachea ;  the  odor  from  the  body  is 
highly  offensive. 

Tests. —  Carbonate  of  Lead  on  a  piece 
of  card  paper,  exposed  to  an  atmosphere 
impregnated  with  this  gas,  is  tm-ned  black 
by  the  formation  of  the  sulphur et  of  lead; 
but  as  the  body  when  undergoing  decom- 
position emits  the  same  kind  of  gas,  this 
test  can  only  be  accepted  as  a  corrobora- 
tive proof. 


III.  — NARCOTICO-ACRID   POISONS. 


These  cause  Death,  either  by  irritation  or  narcotism,  and  sometimes  by  both  combined. 
Their  influence  is  first  local  and  then  remote,  impressing  the  Nervous  System.  They 
are  principally  derived  from  the  Vegetable  Kingdom. 


AGENT. 

NUX    VOMICA    ET    STRYCHNIA. 

Vomic  Nut  and  Strychnia. 

Symptoms.  —  The  vomic  nut  induces  a 
quickened  and  irritable  pulse,  highly  la- 
bored respiration,  snortings,  tetanic  spasms, 
loss  of  muscular  power,  injection  of  the 
mucous  tissues,  extreme  thirst,  and  death 
from  asphyxia ;  previous  to  which  there  is 
intense  suffering.  The  action  of  its  alka- 
loid, strychnia,  is  more  energetic.  It  is 
shown  by  tremors,  followed  by  a  quickness 
of  the  pulse  and  labored  respiration,  ex- 
treme irritability,  loss  of  power  in  the  ex- 
tremities, tetanic  convulsions  increasing  in 
violence,  the  legs  being  thrust  from  the 
body,  the  muscles  rigid,  opisthotonus,  pro- 
fuse   perspiration,    insensibility,    and    the 


pulse  and  respiration  being  scarcely  percep- 
tible ;  the  paroxysm  exists  for  a  few  min- 
utes only,  and  is  followed  by  a  remission 
of  the  symptoms,  leaving  the  animal  much 
exhausted  and  extremely  irritable.  The 
exacerbations,  however,  continue  until  death 
takes  place  from  suffocation. 

Treatment.  —  From  the  tenacity  with 
which  the  powder  of  the  nut  adheres  to  the 
stomach  and  intestines,  it  is  with  difficulty 
dislodged.  Its  removal  may  be  attempted 
by  means  of  active  purgatives,  or  antidotes 
may  be  thrown  in ;  these  consist  of  chlo- 
rine and  of  iodine,  which  form  inert  com- 
pounds with  the  active  principle,  strychnia ; 
but,  as  the  action  of  the  alkaloid  is  on  the 
spinal  marrow  and  the  brain,  little  good  can 
be  hoped  to  be  obtained  when  a  dose  suf- 
ficiently large  to  destroy  life  has  been  given, 


TOXICOLOGICAL   CHART. 


207 


unless  active  measures  be  immediately 
adopted.  If  the  dose  be  not  sufficiently 
large  for  this  purpose,  there  will  be  a  suc- 
cession of  paroxysms,  leaving  behind  them 
much  debility,  which  is  to  be  counteracted 
by  tonics  and  diffusible  stimulants,  with, 
perhaps,  counter-irritants  along  the  course 
of  the  spine,  lest  effusion  should  take 
place. 

Morbid  Appearances.  —  Mucous  lining  of 
the  alimentary  tube  inflamed,  lungs  gorged 
with  blood,  and  the  vascular  system  through- 
out the  body  in  a  state  of  congestion.  The 
spinal  canal  much  inflamed.  Effusion  of 
bloody  serum  into  the  theca  vertebralis ; 
motor  division  of  the  spinal  cord  more  in- 
jected than  the  other,  and  the  nerves  taking 
their  origin  from  it  inflamed.  The  mem- 
branes of  the  brain  have  been  found  in- 
flamed, with  effusion  on  the  surface  of  the 
cerebellum,  and  a  softening  of  the  whole 
cortical  portion  of  the  brain.  Rigidity  of 
the  muscles  of  the  body.  Rapid  decompo- 
sition, accompanied  with  much  foetor. 

Tests.  —  The  powder  of  the  nut  has  a 
greenish-gray  color,  an  intensely  bitter  taste, 
and  the  odor  of  liquorice.  Being  collected, 
it  is  to  be  boiled  in  water  acidulated  with 
sulphuric  acid,  filtered,  and  the  solution 
neutralized  by  carbonate  of  lime  and  evap- 
orated to  dryness.  The  dry  mass  being 
acted  upon  by  successive  portions  of  alco- 
hol, these  are  to  be  evaporated  to  the  con- 
sistence of  syrup,  when  the  product  will  be 
found  to  have  an  intensely  bitter  taste,  and 
it  becomes  of  a  deep  orange-red  color  with 
nitric  acid,  which  color  is  desti'oyed  by  the 
protochloride  of  tin.  Sometimes  it  de- 
posits crystals  of  strychnia  on  standing. 
These  tests  will  also  be  available  for  the 
alkaloid ;  to  which  may  be  added  its  spar- 
ing solubility  in  water,  the  alkaline  reaction 
of  its  alcoholic  solution,  and  its  forming 
neutral  and  crystallizable  salts  with  acids. 

AGENT. 

SEMEN    CROTONI. 

Croton  Seed. 
Symptoms.  —  This   purgative,  when    in- 
cautiously administered,  has  produced  death 


by  inducing  violent  inflammation  of  the 
intestinal  canal,  followed  by  superpurga- 
tion ;  the  alvine  dejections  being  profuse, 
watery,  and  offensive. 

Treatment.  —  A  free  use  of  demulcents, 
with  astringents,  as  catechu,  opium,  and 
chalk.  Bloodletting ;  opiate  enemas.  Hot 
rugs  to  the  abdomen,  counter  irritants,  etc. 

Morbid  Appearances.  —  Violent  inflam- 
mation of  the  intestines,  particularly  the 
caecum  and  colon,  involving  all  the  tunics, 
the  mucous  lining  being  easily  torn.  Fae- 
ces abundant  and  semi-fluid.  Lungs  in  a 
state  of  congestion. 

Tests.  —  None  definite. 

A  GENT. 

DIGITALIS    PURPUREA. 

Fox  Glove. 

Symptoms. —  Languor,  gastric  irritation, 
coldness  of  the  body  and  extremities,  pale- 
ness of  the  mucous  tissues,  cold  and  clam- 
my perspiration,  quickened  and  feeble  pulse, 
death. 

When  it  accumulates  in  the  system,  af- 
ter having  been  repeatedly  given  in  compar- 
atively small  doses,  it  produces  loss  of 
appetite,  nausea,  languor,  a  quick  and  irreg- 
ular pulse,  followed  by  purgation,  and  the 
effects  then  gradually  disappear. 

Treatment.  —  Expulsion  of  the  agent  by 
means  of  a  solution  of  aloes,  combined 
with  linseed  oil.  The  free  use  of  demul- 
cents ;  diffusible  stimulants ;  counter-irri- 
tants. 

Morbid  Appearances.  —  Depending  upon 
the  condition  and  previous  state  of  the 
animal.  If  much  debilitated,  inflammation 
of  the  mucous  lining  of  the  stomach  and 
alimentary  tube  may  be  seen  to  exist.  At 
other  times  no  trace  of  its  influence  on  any 
of  the  tissues  can  be  detected,  and  it  is  then 
supposed  to  cause  death  by  exhaustion  of 
the  nervous  energy. 

Tests.  —  None  definite. 

AGENT. 

VERATRUM  ALBUM. 

White  Hellebore. 
Symptoms.  —  Efforts   to   vomit,   acceler- 


208 


TOXICOLOGICAL    CHART. 


ated  pulse,  untranquil  respiration,  intestinal 
ii-ritation,  Avhich,  if  followed  by  purging, 
alfords  relief;  if  not,  these  symptoms  be- 
come more  urgent,  the  body  is  covered  with 
])crspiration,  saliva  is  secreted  in  increased 
quantities,  the  legs  become  deathly  cold, 
inflammation  of  the  bowels  supervenes,  and 
death. 

Treatment.  —  A  free  use  of  demulcents. 
]\Iilk  has  been  strongly  advocated ;  on  what 
grounds  beyond  that  of  its  being  a  bland 
fluid,  I  am  at  a  loss  to  conjecture.  Olea- 
ginous purgatives ;  counter-irritants. 

Morbid  Appearances.  —  The  villous  coat 
of  the  stomach  will  be  found  inflamed;  the 
intestines  also  in  a  high  state  of  inflamma- 
tion, particularly  the  caecum  and  colon;  the 
heart  pale  and  flabby ;  and  the  lungs  con- 
gested. 

Tests.  —  None  definite. 

AGENT. 

NICOTIANA    TABACUM. 

Tobacco. 

Symptoms.  —  Nausea,  giddiness,  coma, 
feeble  and  irritable  pulse.  Sometimes  gen- 
eral excitement  of  the  system,  profuse  per- 
spiration, labored  respiration,  pulse  much 
quickened,  partial  insensibility. 

Treatment. — Expulsion  of  the  agent  by 
purgatives ;  diffusible  stimulants  when  coma 
exists ;  demulcents. 


Morbid  Appearances.  —  I  am  not  ac- 
quainted with  an  instance  of  death  having 
taken  place,  although  this  agent  is  fre- 
quently given  as  a  vermifuge  in  very  large 
quantities. 

Tests.  —  None  definite. 

AGENT. 

JUNIPERUe    SABINA. 

Savin. 

Sy7nptoms.  —  This,  like  the  preceding 
agent,  is  given  as  a  vermifuge,  and  some- 
times incautiously.  Gastric  irritation  is 
then  evinced,  the  animal  refuses  food,  and 
is  languid  ;  this  is  followed  by  diuresis,  and 
sometimes  by  purging ;  the  pulse  becomes 
irregular  and  full,  and  the  respiration  hur- 
ried. 

Treatment.  —  Expulsion  of  the  agent 
from  out  the  alimentary  canal  by  oleagi- 
nous purgatives ;  demulcents. 

Morbid  Appearances.  —  Esophagus  and 
stomach  inflamed,  particularly  the  villous 
portion  of  the  latter  viscus,  on  which  patches 
of  extravasated  blood  are  seen  to  exist ;  the 
small  intestines  contain  miuch  raiucus,  and 
are  slightly  inflamed ;  lungs  congested ; 
larynx  and  trachea  of  a  rusty  yellow  color  ; 
glands  at  the  root  of  the  tongue  much 
enlarged. 

Tests.  —  The  partially  digested  vegeta- 
ble matter  found  in  the  alimentary  tube, 
which  may  be  distinguished  by  its  odor. 


Under  the  head  of  Narcotico- Acrid  Poisons,  perhaps,  should  be  placed  the  Atropa 
Belladonna,  Deadly  Nig-htshade,  which,  in  large  doses,  induces  singultus,  a  dilatation 
of  the  pupils,  feeble  and  irritable  pulse,  and  a  relaxed  state  of  the  bowels.  Also  many 
of  the  umbelUferous  order  of  plants,  as  Conium  Maculatum,  Common  Hemlock,  the 
influence  of  which  is  probably  that  of  a  Narcotic ;  Cicuta  Virosa,  Water  Hemlock, 
which,  to  some  animals  proves  an  energetic  Poison ;  wdth  a  few  of  the  natural  family 
of  the  Ranunculaca3,  as  the  Aconitum  Napellus,  Monkshood,  and  Helleboris  Niger, 
Black  Hellebore,  which  cause  death  by  irritation,  producing  gastro-enteritis,  followed  by 
delirium;  likewise  Delphinium  Staphysagria,  Stave sacre ;  Bryonia  Alba,  Wild-vine 
or  Bryony,  and  Felis  Foemina,  Female  Fern;  of  which  latter  very  large  quantities  are 
required  to  effect  any  marked  change  in  the  animal  system ;  and,  indeed,  it  may  be  said 
of  the  Vegetable  Poisons  generally,  that  the  Horse  is  enabled  to  resist  the  influence 


TOXICOLOGIC AL    CHAET.  209 

of  comparatively  immense  doses  of  them,  which  in  all  probability  arises  from  the 
peculiar  structure  of  his  stomach. 

Wheat  and  Barley  have  been  designated  as  poisons  to  this  animal ;  and  occasionally 
they  have  proved  to  be  so,  by  setting  up  acute  gastritis.  A  very  common  sequela  of 
poisoning  by  Wheat  is  inflammation  of  the  laminsB,  the  result  of  metastasis ;  and  of 
Barley,  a  depilation  of  the  sldn.  We  are,  however,  in  want  of  more  correct  information 
than  at  present  we  possess,  before  anything  definite  can  be  laid  down  under  this  head, 
as  both  wheat  and  barley,  given  in  moderate  quantities  and  with  judgment,  often  prove 
beneficial. 

I  am  induced  to  pass  the  agents  above  enumerated  thus  cursorily  over,  my  object 
having  been  to  give  a  condensed  and  tabular  view  of  such  substances  as  are  known  to 
destroy  life  in  the  horse  when  incautiously  or  maliciously  administered,  and  to  elucidate 
a  Thesis  on  Poisons  which  I  had  the  honor  to  read  before  the  Members  of  the  Veteri- 
nary Medical  Association  in  1836  :  at  the  same  time,  I  hope  that  this  attempt  may 
prove  of  some  use  to  the  Student  of  Veterinary  Medicine. 

27 


EXPLANATION   OF   FIGURE   XX. 


THE  HEAD. 

a.  Orbicularis  palpebrarum. 

6.  Levator  palpebrse. 

c.  Dilator  naris  lateralis. 

d.  Dilator  naris  anterior. 

e.  e.  Orbicularis  oris,  the  circular  muscle  of  the  mouth  ;  the  letters  are  rather  too 

low  to  indicate  the  muscle. 

f.  Nasalis  longus. 

g.  Levator  labii  superioris. 

k.     Masseter.  » 

m.   Attolentes  et  abducens  aurem. 

THE  NECK, 
c".    Trachelo  subscapularis,  —  Scalenus. 
s.     Splenius. 

r.  t.  Tendon  of  the  splenius  and  complexus  major. 
u.     Levator  humeri. 

V.     Sterno  niaxillaris.     The  jugular  vein  is  here  shown  between  the  two  preceding 
muscles. 

THE  SHOULDER  A>D  FORE  EXTREMITIES. 

e".    Sterno  scapulari.  —  Pectoralis  parvus. 

f".  Antea  spinatus. 

g".  Postea  spinatus. 

h.     Teres  major. 

m".  n".  Triceps  extensor  brachii. 

I.     Scapulo  ulnaris. 

o".   Pectoralis  transversalis. 

P".  u".  Flexor  metacarpi  extemus. 

r.  "  "        intemus. 

r".  Knee  joint. 

s".  5.  Extensor  metacarpi  magnus. 

t.     Extensor  metacarpi  obliquus. 

u\  v".  V.  Tendons  perforans  and  perforatus. 

y".  y".  Extensor  sufl&raginis. 

z".  «".  Pastern  joint. 

8.  8.  Extensor  tendons. . 

6.     Radial  vein. 

g.    Flexor  pedis. 

ABDOMINAL  REGION. 

6.  Intercostales. 

c.  Transversalis  abdominis  extemus. 

d.  "  "         intemus. 
D.    Serratus  magnus. 

J.    Pectoralis  magnus. 

7.  The  sheath. 

4.    Superficial  thoracic  van. 


EXPLANATION    OF    FIGURE   XX.    CONTINUED. 

POSTERIOR    EXTREMITIES. 
e\    Erector  coccygis. 
9.     Compressor  coccygis. 
h".  i.  The  three  glutei. 
J'.  Triceps. 
k'.  l:  Biceps  abductor  tibialis. 

5.  Tibia. 

6.  X.  X.  g.  Fleshy  belly  of  the  extensors. 
V.     Peroneus. 

n\   Rectus. 

0\  Vastus  cxternus. 

r.     Gastrocnemi  internus. 

vTu.  u.  V.  Gastrocnemi. 

y.  X.  X.  8.  Extensor  tendons. 

X.  u.  (Off  leg.)    Flexors  perforans  et  perforatus. 


DICTIONARY  OF  VETERINARY  SCIENCE 


CONTAINING 


MANY  PRACTICAL    OBSERVATIONS, 


OF  MUCH   IJIPORTANCE  TO 


HUSBANDMEN     AND     HORSE     OWNERS 


SELECTED  FROM  VARIOUS  SOURCES,  WITH  ADDITIONS. 

(211) 


A  DICTIONARY  OF  VETERINAEY  SCIENCE. 


Abdomen. —  That  part  of  the  animal 
usually  denominated  the  belly.  This  cavity 
contains  the  intestines,  or  bowels,  liver, 
spleen,  pancreas,  kidneys,  etc.,  and  is  sepa- 
rated from  the  thorax,  or  chest,  by  the 
diaphragm. 

Abortion. —  Our  attention  was  called,  a 
short  time  ago,  to  a  mare,  about  eight  years 
old,  said  to  be  laboring  under  colic.  She 
had  been  driven  very  fast  during  the  early 
part  of  the  day  ;  and  about  noon,  when  we 
saw  her  in  the  stable,  she  seemed  to  mani- 
fest considerable  uneasiness.  The  surface 
of  the  body  was  cold,  pulse  small  and  in- 
termittent. The  genitals  were  considerably 
swollen,  and  a  slight  discharge  from  the 
vagina  was  observed.  She  had  occasional 
uterine  pains,  which,  however,  were  very 
feeble. 

We  immediately  gave  the  following  dif- 
fusible stimulant : 

Powdered  grains  of  paradise,  1  drachm. 

"  bethroot  {trillium  purpureum)     i  di-achm. 
Hot  water,  1  quart. 

This  was  administered  from  a  bottle.  In 
a  few  minutes,  the  parturient  process  com- 
menced, and  she  shortly  gave  birth  to  a 
dead  foetus.  The  mare  was  in  her  fifth 
parturient  month.  She  was  put  on  a  gen- 
erous diet,  and  rapidly  convalesced  without 
any  after  treatment. 

Remarks.  —  Great  care  and  gentleness 
should  be  exercised  toward  mares  during 
pregnancy.  Hard  work  in  harness,  over 
bad  roads,  is  likely  to  produce  abortion ; 
and  mares  that  have  once  aborted  are  liable 
to  a  recurrence  of  the  same.  Light  work 
and  moderate  exercise,  however,  are  essen- 
tial to  their  general  health. 

When  the  period  of  foaling  draws  nigh, 
the  mare  should  be  separated  from  her  com- 
panions.     Having   foaled,   she  should   be 


turned  into  a  pasture,  where  there  is  a  barn. 
The  foal  may.  be  weaned  at  six  months ;  if 
it  should  die,  or  be  taken  from  the  dam, 
humanity  would  suggest  the  propriety  of  a 
few  weeks'  rest,  to  enable  the  mother  to  re- 
cover from  the  effects  of  parturition. 

Miscarriage,  slipping,  or  slinking  foal  or 
calf,  ivarping.  —  In  mares,  miscarriage  is 
very  generally  caused  by  over-exertion  dur- 
ing the  latter  period  of  gestation.  It  is  not 
unfrequently  brought  about  by  accidents  at 
grass,  such  as  falling  in  a  ditch  or  hole,  and, 
struggling  violently  to  extricate  themselves. 
Kicks  on  the  belly  are  by  no  means  an  un- 
common cause  of  miscarriage ;  for  which 
reason,  a  mare,  when  near  her  time,  should 
be  kept  by  herself:  after  foaling  she  will 
reqiiire  a  few  weeks'  rest,  in  order  to  re- 
cover from  the  effects  of  parturition ;  and, 
when  first  brought  into  work  again,  the 
services  required  of  her  should  be  very 
slight.  Exposure  to  wet  and  cold  will  oc- 
casion miscarriage ;  also,  high  feeding  and 
want  of  proper  exercise.  Abortion  is  of 
more  frequent  occurrence  in  sheep  than  in 
mares,  and  is  caused  by  fright,  overdriving, 
and  being  worried  by  dogs,  and  by  being 
kept  in  cold,  damp  situations,  and  on  im- 
proper food. 

Cows  are  particularly  liable  to  the  ac- 
cident of  warping,  or  slinldng  the  calf. 
The  common  cause  of  abortion  is  improper 
feeding.  The  filthy,  stagnant  water  they 
are  often  compelled  to  drink  is  likewise  a 
serious  cause,  not  only  of  abortion,  but 
also  of  general  derange^ment  of  the  animal 
functions.  Dr.  White  states  that  "  a  farm 
in  Gloucestershire  had  been  given  up  three 
successive  times  in  consequence  of  the  loss 
the  owners  sustained  by  abortion  in  their 
cattle  :  at  length  the  fourth  proprietor,  after 
suffering  considerably  in  his  live  stock  for 

(213) 


214 


A   DICTIONARY. 


the  first  five  years,  suspected  that  the  water 
of  his  ponds,  which  was  extremely  filthy, 
might  be  the  cause  of  the  mischief;  he 
therefore  dug  three  wells  upon  his  farm,  and, 
having  fenced  round  the  ponds  to  prevent 
his  cattle  from  drinldng  there,  caused  them 
to  be  supplied  with  the  well-water  in  stone 
troughs  erected  for  the  purpose ;  and  from 
this  moment  his  live  stock  began  to  thrive, 
and  the  quality  of  the  butter  and  cheese 
made  on  his  farm  was  greatly  improved. 
Li  order  to  show,"  says  the  same  author, 
"  that  the  accident  of  warping  may  arise 
from  a  vitiated  state  of  the  digestive  organs, 
I  will  here  notice  a  few  circumstances  tend- 
ing to  corroborate  this  opinion.  In  1782,  all 
the  cows  in  possession  of  farmer  D'Euruse, 
in  Picardy,  miscarried.  The  period  at 
which  they  warped  was  about  the  fourth  or 
fifth  month.  The  accident  was  attributed 
to  the  excessive  heat  of  the  preceding  sum- 
mer ;  but,  as  the  water  they  were  in  the 
habit  of  drinking  was  extremely  bad,  and 
they  had  been  kept  upon  oat,  wheat,  and 
and  rye  straw,  it  appears  to  me  more  prob- 
able that  the  great  quantity  of  straw  they 
were  obliged  to  eat,  in  order  to  obtain  suf- 
ficient nourishment,  and  the  injury  sustained 
by  the  third  stomach,  in  expressing  the  fluid 
parts  of  the  masticated  or  ruminated  mass, 
together  with  the  large  quantity  of  water 
they  drank,  while  kept  on  this  dry  food,  was 
the  real  cause  of  their  miscarrymg. 

"  A  farmer  at  Chareton,  out  of  a  dairy 
of  twenty-eight  cows,  had  sixteen  slip  their 
calves  at  different  periods  of  gestation. 
The  summer  had  been  very  dry,  and,  during 
the  whole  of  this  season,  they  had  been 
pastured  in  a  muddy  place,  which  was 
flooded  by  the  Seine.  Here  the  cows  were 
generally  up  to  their  knees  in  mud  and 
water.  In  1789,  all  the  cows  in  a  village 
near  Mantes  miscarried.  All  the  land  in 
this  place  was  so  stiff  as  to  hold  water  for 
some  time;  and,  as  a  vast  quantity  of 
rain  fell  that  year,  the  pastures  were  for  a 
long  time  completely  inundated,  on  which 
account  the  grass  became  bad  :  this  shows 
that  keeping  cows  on  food  that  is  deficient 
in  nutrition,  and  difficult  of  digestion,  is 


one  of  the  principal  causes  of  miscarriage." 
It  is  supposed  that  the  sight  of  a  slipped 
calf,  the  smell  of  putrid  animal  substance, 
is  apt  to  produce  warping.  Some  curious 
cases  of  abortion  which  arc  worthy  of  notice 
happened  in  the  dairy  of  a  French  farmer. 
For  thirty  years  his  cows  had  been  subject 
to  abortion.  His  cow-house  was  large  and 
well  ventilated ;  his  cows  were  in  apparent 
health ;  they  were  fed  like  others  in  the  vil- 
lage ;  they  drank  the  same  water ;  there 
was  nothing  different  in  the  pasture ;  he 
had  changed  his  servants  many  times  in  the 
course  of  thirty  years ;  he  pulled  down  the 
barn  or  cow-house,  and  built  another,  on  a 
different  plan  ;  he  even,  agreeably  to  super- 
stition, took  away  the  aborted  calf  through 
the  window,  that  the  curse  of  future  abor- 
tion might  not  be  entailed  on  the  cow  that 
passed  over  the  same  threshold.  To  make 
all  sure,  he  had  broken  through  the  wall  at 
the  end  of  the  cow-house,  and  opened  a  new 
door.  But  still  the  trouble  continued. 
Several  of  his  cows  had  died  in  the  act  of 
abortion,  and  he  had  replaced  them  by  others : 
many  had  been  sold,  and  their  vacancies 
filled  up.  He  was  advised  to  make  a  thor- 
ough change.  This  had  never  occurred  to 
him ;  but  at  once  he  saw  the  propriety  of 
the  counsel.  He  sold  every  beast,  and  the 
pest  was  stayed,  and  never  appeared  in  his 
new  stock.  This  was  owing,  probably,  to 
sympathetic  influence ;  and  the  result  of 
such  influence  is  as  fatal  as  the  direct  con- 
tagion."    (See  Youatt.) 

The  usual  symptoms  preceding  abortion 
are  a  sudden  filling  of  the  udder,  and  a 
loose,  flabby,  and  sometimes  swollen  ap- 
pearance of  the  genitals,  which  discharge  a 
Uttle  red-colored  fluid.  The  lancet  and 
medicine  have  been  resorted  to  with  very 
little  success.  Both  of  them  are  decidedly  in- 
jurious ;  the  animal  should  be  put  into  some 
dry,  sheltered  place,  by  herself,  and  kept  on 
boiled  mashes  and  gruel  for  a  few  days. 

Absorbents. —  Medicines  which  are  giv- 
en in  view  of  absorbing  gas  or  neutralizing 
acidity  in  the  digestive  caAdty. 

Absorbent  Vessels.  —  (See  Lacteals, 
part  first.) 


A   DICTIONARY. 


215 


Absinthium. — Common  wormwood,  used 
for  the  purpose  of  reducing  swellings  that 
have  resulted  from  violence.  Two  ounces 
of  wormwood  are  steeped  in  one  quart  of 
New  England  rum  ;  if  a  limb  of  the  ani- 
mal is  involved,  the  wormwood  is  then 
bound  on  with  bandages,  and  the  parts 
occasionally  wetted  with  the  fluid. 

Acacia. —  Gum  arable,  used  as  a  demul- 
cent and  lubricant.  In  poisoning,  it  is  use- 
ful to  sheathe  the  membranes  of  the  stomach 
and  alimentary  canal,  and  will  defend  them 
from  the  action  of  drastic  purges. 

Acacia  Catechu.  —  Gum  catechu.  This 
is  a  powerful  astringent :  it  is  obtained  from 
a  tree  that  grows  in  Japan. 

Acetabulum. —  The  socket  in  which  the 
head  of  the  thigh  bone  is  l5dged. 

AcETATED  Liquor  of  Ammonia. —  This 
has  been  long  known  by  the  popular  term 
of  Mindererus'  spirit,  and  is  made  by  pour- 
ing any  quantity  of  acetic  acid,  diluted  with 
seven  times  its  amount  of  water,  upon  car- 
bonate of  ammonia,  until  all  fermentation 
ceases,  or  until  a  neutral  solution  has  been 
formed.  It  is  useful  in  horse  practice ;  it 
gently  invigorates,  is  diaphoretic,  and  some- 
times it  proves  mildly  diuretic.  It  princi- 
pally shows  its  salutary  effects  in  the  com- 
mencement of  the  febrile  stage,  or  at  the 
close  of  lingering  febrile  diseases,  particular- 
ly of  influenza.  In  the  more  early  stages  of 
epidemic  catarrh,  it  may  also  be  exhibited  : 
the  dose  is  from  four  ounces  to  an  almost 
unlimited  quantity.  The  author  used  this 
preparation  with  remarkable  success  in  the 
treatment  of  influenza,  which  prevailed,  in 
Massachusetts,  in  the  fall  and  winter  of 
1855.  The  dose  for  horses  and  cattle  is 
from  three  to  four  fluid  ounces.  It  is  gen- 
erally given  diluted  with  an  equal  quan- 
tity of  water. 

Acids. —  Are  distinguished  by  their  sour 
taste ;  they  readily  combine  with  alkalies, 
producing  effervescence.  Those  commonly 
used  in  veterinary  practice  are :  sulphuric, 
nitric,  hydrochloric,  and  acetic.  They  are  all 
more  or  less  corrosive,  and  decompose  the 
vital  tissues,  by  uniting  with  their  serous, 
albuminous,  and  saline  constituents.    There- 


fore, when  administered  to  the  horse,  they 
should  be  diluted  with  water. 

Aconita. —  Wolfsbane. —  A  powerful 
sedative ;  it  moderates  the  action  of  the 
heart,  and  produces  depression  of  the  vital 
energies.  It  is  generally  used  in  the  form 
of  tincture.    Dose,  from  ten  to  fifteen  drops. 

Action.  —  The  gait  of  a  horse  ;  which  de- 
pends on  his  powers  and  the  mode  of 
training. 

Action  of  Medicines.*  —  Every  medi- 
cine is  endowed  with  certain  inherent  char- 
acteristic actions,  which  distinguish  it  as 
decidedly  as  its  physical  and  chemical  pro- 
perties. Thus,  some  medicines  act  on  the 
bowels,  causing  purgation ;  others  on  the 
kidneys,  stimulating  the  secretion  of  urine ; 
and  others  on  the  brain  and  nervous  sys- 
tem, causing  insensibility ;  in  fact,  there 
is  no  part  or  organ  of  the  body,  except  the 
spleen  and  pancreas,  which  is  not  influ- 
enced, and  that  often  in  several  different 
ways,  by  some  medicinal  agent.  It  is  im- 
possible, however,  to  explain  why  a  medi- 
cine should  act  in  one  way  rather  than  in 
another ;  why,  for  example,  aloes  is  purga- 
tive, and  not  diuretic,  narcotic, or  anaesthetic; 
or  why  chloroform  is  anaesthetic,  and  not 
vesicant,  diuretic,  or  purgative.  The  stu- 
dent must  therefore  endeavor  to  conceive  of 
these  actions,  or  dynamical  effects  of  medi- 
cines, in  the  same  manner  as  he  does  of 
their  more  familiar  properties  of  color,  odor, 
taste,  or  density. 

Some  medicines,  as  demulcents,  caustics, 
and  astringents,  have  merely  a  local  or  topi- 
cal action — soothing,  irritating,  corroding, 
or  altering  the  animal  tissues,  but  not  ex- 
tending their  influence  beyond  the  part  to 
which  they  are  first  applied.  Others,  either 
with  or  without  such  a  local  effect,  have  a 
remote  or  indirect  action  on  organs  at  a 
distance  from  the  part  with  which  they  are 
first  brought  in  contact.  Medicines  which 
act  thus  remotely  or  indirectly  are  thought 
to  produce  their  effects  in  either  or  both  of 
the  two  following  ways :  (a)  They  are 
absorbed  into  the  circulation,  and  carried 
by  the  blood  to  remote  organs ;  or  (b),  The 

*  Finlay  Dini. 


216 


A   DICTIONARY. 


impression,  which  they  produce  on  the  parts 
with  which  they  are  first  brought  in  contact, 
is  transmitted  along  the  nerves  to  other 
parts.  The  latter  mode  of  operation  is 
sometimes  called  action  by  sympathy. 

(a.)  The  great  majority  of  medicines  ap- 
pear to  act  in  the  former  of  these  two  ways, 
being  taken  up  by  the  blood-vessels  from 
the  sm-face  of  the  mucous  membranes,  sldn, 
or  other  part  to  which  they  have  been  ap- 
plied. Thus,  most  medicines  given  by  the 
mouth,  after  having,  if  solid,  undergone 
solution  in  the  acid  gastric  juice  or  alkaline 
bile,  pass,  by  a  process  of  endosmose,  into 
the  capillary  veins  which  ramify  on  the  sur- 
face of  the  stomach  and  intestines,  enter 
the  general  circulation  by  the  mesenteric 
and  portal  vessels,  and  are  thus  carried  to 
all  parts  of  the  body,  altering,  it  may  be, 
the  nutritive  processes  of  various  organs 
and  tissues,  and  at  length  expelled  through 
some  of  the  excretory  channels,  as  the  skin, 
kidneys,  or  bowels.  The  rapidity  with 
which  most  substances  are  thus  absorbed, 
and  make  the  round  of  the  circulation,  is 
almost  incredible.  Professor  Hermg,  of  the 
Veterinary  College,  Stuttgardt,  found  that 
yellow  prussiate  of  potash  injected  into  one 
of  the  jugular  veins  of  a  horse  appeared  in 
the  other  in  twenty-five  seconds,  and  was 
exhaled  from  the  mucous  and  serous  mem- 
branes in  a  few  minutes.;  and  also  that 
chloride  of  barium  injected  into  the  jugular 
vein  of  a  dog  reached  the  carotid  artery  in 
seven  seconds.  Dr.  Blake  observed  that 
chloride  of  barium  and  nitrate  of  baryies 
traversed  the  whole  circulation  of  a  dog  in 
nine  seconds,  and  that  of  a  horse  in  twenty 
seconds;  and  a  similar  rapidity  of  distri- 
bution doubtless  obtains  with  substances 
which  cannot  easily  be  detected  in  the  blood. 

(b.)  The  other  hypothesis,  regarding  the 
action  of  medicines,  is  that  they  owe  the 
development  of  their  effects  to  the  produc- 
tion of  some  nervous  impression  on  the 
part  to  which  they  are  first  applied,  and  its 
subsequent  transmission  to  remote  organs 
by  means  of  the  nervous  system.  A  recent 
modification  of  this  theory,  advanced  by 
Messrs.  Morgan  and  Addison,  assumes  that 


the  nervous  impression  is  produced,  not 
upon  the  part  with  which  the  medicine  is 
first  brought  in  contact,  but  on  the  interior 
of  the  blood-vessels  after  partial  absorption. 
Part  of  the  evidence  in  support  of  these 
hypotheses  is  derived  from  the  fact  that 
some  poisons  operate  with  such  extreme 
rapidity  as  to  render  it-  doubtful  whether 
there  could  be  time  for  their  being  absorbed 
and  making  the  round  of  the  circulation. 
Thus:  anhydrous  prussic  acid,  conia  the 
alkaloid  of  hemlock,  and  aconita  the  alka- 
loid of  aconite,  when  injected  into  the 
veins,  applied  to  the  cellular  tissue,  or  given 
by  the  mouth,  produce  almost  instantaneous 
effects,  and  death  in  a  few  seconds.  It  ap- 
pears, however,  that  the  strongest  evidence 
in  favor  of  the  theories  under  consideration 
consists  in  the  effects  of  local  injuries  in 
producing  constitutional  disturbance.  For 
example,  a  blow  on  the  region  of  the 
stomach  sometimes  causes  fatal  swooning ; 
distention  of  the  stomach  often  produces 
hiccough ;  the  presence  of  worms  in  the 
intestines  sometimes  induces  epilepsy ;  and 
a  local  injury  frequently  causes  fever  and 
constitutional  distm-bance  of  all  the  more 
important  organs  of  the  body.  In  such 
cases  the  connection  between  cause  and 
effect  obviously  depends  on  the  transmis- 
sion of  nervous  impressions  only.  And  if 
topical  causes  are  thus  productive  of  remote 
effects,  it  is  siu"ely  fair  to  infer  that  medi- 
cines and  poisons  may  operate  in  a  similar 
manner. 

In  fine,  although  it  would  appear  that 
most  medicines  are  absorbed  and  actually 
conveyed  to  the  parts  on  which  they  act, 
and  that  such  absorption  and  actual  con- 
tact are  essential  to  their  action,  yet  it  is 
highly  probable  (though  not  yet  positively 
ascertained)  that  some  substances,  espe- 
cially the  more  active  poisons,  astringents, 
and  emetics,  owe  their  effects  to  the  pro- 
duction of  a  nervous  impression,  and  its 
propagation  to  remote  organs.  Nor  is  it  at 
all  improbable  that,  under  different  modify- 
ing influences,  certain  substances  will  oper- 
ate sometimes  in  one  and  sometimes  in 
the  other  of  these  two  ways. 


A   DICTIONARY. 


217 


Actual  Cautery. — Red-hot  iron.  (See 
Firing.) 

Acute. —  A  term  applied  to  those  diseases 
which  are  sudden  in  their  attack  and  vio- 
lence, accompanied  with  great  pain. 

Acute  Indigestion  in  Cattle,  called 
Hove,  or  Blown.  —  When  cattle  have  be- 
come fatigued  by  driving  or  by  long  fasting, 
and  suddenly  find  themselves  with  plenty 
of  food  before  them,  particularly  such  as 
requires  little  mastication,  as  chaff,  bran, 
grains,  etc.,  etc. ;  and  also  at  aU  times 
when  they  meet  with  food  they  have  long 
been  deprived  of,  as  various  artificial  grasses, 
particularly  red  clover,  they  are  apt  to  eat 
greedily,  and  omit  to  stop  for  the  purposes 
of  rumination ;  by  which  means  the  rumen 
or  paunch  becomes  so  distended  as  to  be 
incapable  of  expelling  its  contents.  From 
this,  fermentation  begins  to  take  place,  and 
a  large  quantity  of  gas  escapes,  which  in- 
creases the  distention,  until  the  stomach, 
by  its  pressure  on  the  diaphragm,  suffocates 
the  animal. 

The  sijmptoriis  are  uneasiness  and  distress, 
vni\\  quickened  respiration ;  sometimes  there 
is  a  degree  of  phrensy  present.  When  it  is 
occasioned  by  green  food,  the  evolution  of 
gas  is  enormous,  and  the  tympanitis  gives 
a  drum-like  distention  to  the  belly;  but 
when  dry  food,  as  chaff,  bran,  etc.,  etc.,  has 
been  taken,  the  impacted  matter  does  not 
distend  so  quickly,  and  the  symptoms  are 
less  acute ;  they  resemble  those  of  constipa- 
tion ;  and  sounding  the  side  gives  back  a 
response  as  though  a  solid  matter  were  hit 
against.  It  is  thought  to  be  more  likely  to 
occur  in  warm  and  wet  weather  than  in  any 
other ;  and,  if  such  be  the  case,  it  must  arise 
from  the  state  of  the  vegetable  matter  and 
the  surrounding  warmth  both  being  favor- 
able to  fermentation. 

The  treatment  will  consist  in  attempting 
to  lessen  the  distention  by  evacuating  the  dis- 
tending gas,  or  otherwise  trying  to  neutralize 
it.  Purgatives  have  little  or  no  effect.  The 
evacuation  of  the  gases  is  effected  by  the 
introduction  of  a  probang,  which  is  passed 
down    the    esophagus  ;    or   it    is   brought 

about  by  puncturing  the  side,  when  the  dis- 
28 


tention  is  urgent,  or  the  want  of  assistance 
renders  it  imperative  to  evacuate  the  gas 
immediately,  to  prevent  suffocation ;  a 
puncture  is  therefore  at  once  made  into  it, 
which,  among  graziers,  is  called  paunching. 
When  nothing  better  is  at  hand,  this  may 
be  performed  with  a  lancet,  or  even  a  pen- 
knife ;  the  wound  made  being  kept  open  by 
the  introduction  of  a  piece  of  hollow  elder 
or  common  wood;  the  place  of  puncture 
being  midway  between  the  ileum  or  haunch- 
bone  and  the  last  rib,  a  span  below  the 
transverse  processes  of  the  lumbar  vertebrae 
on  the  left  side,  to  which  the  first  stomach 
or  paunch  inclines.  A  cattle  trocar  will, 
however,  permit  the  gas  to  escape  with  cer- 
tainty and  speed,  and  should  always  be 
used  to  make  the  puncture,  in  preference  to 
any  other  instrument.  As  soon  as  the  air 
is  perfectly  evacuated,  and  the  paunch  is 
observed  to  resume  its  office,  the  trocar 
may  be  removed ;  the  v/ound  being  care- 
fully closed  by  a  pitch  plaster,  or  other  ad- 
hesive matter.  It  is  necessary  to  observe, 
that  this  operation  is  so  simple  and  safe, 
that,  whenever  a  medical  assistant  cannot 
be  obtained,  no  person  should  hesitate  a 
moment  about  doing  it  himself.  The  do- 
mestic remedies  for  lessening  the  distention, 
by  condensing  the  gas,  have  been  various ; 
as  oil  of  turpentine,  and  particularly  am- 
monia, a  strong  solution  of  which  in  water 
has  been  found  serviceable.  The  allcalies 
generally  have  long  been  used  with  variable 
success.  Vinegar,  in  the  Quarterly  Journal 
of  Agricidture,  is  strongly  recommended; 
but,  as  it  is  observed  that  the  elastic  fluids 
developed  are  not  always  alike,  so  the  effects 
resulting  from  the  most  reputed  agents  have 
too  often  failed.  Mr.  Youatt  recommends 
the  introduction  o£  chlorinated  lime,  given 
in  doses  of  from  3ij  to  3iv  suspended  in 
water. 

But  it  is  to  a  foreign  veterinarian  we  are 
indebted  for  the  best  agent  for  neutralizing 
the  gases  given  off  when  the  rumen  is  dis- 
tended. M.  Charlet  has  recommended  the 
chloride  of  potash,  which  substance  has  a 
great  affinity  for  the  compounds  of  hydi'o- 
gen  that  usually  form  the  major  portion  of 


218 


A  DICTIONARY. 


those  which  exist  in  the  stomach.  This 
substance  is  to  be  given  in  doses  of  an 
ounce  to  a  horse,  half  an  ounce  to  a  cow, 
and  three  drachms  to  a  sheep.  Occasion- 
ally, however,  from  the  contents  of  the 
stomach  being  in  a  state  of  fermentation, 
no  gas  will  escape,  upon  the  probang  or 
trochar  being  introduced.  The  chloride  of 
potash  is  then  to  be  poured  down  the  pro- 
bang  or  trochar,  which  ever  may  be  used ; 
and  this  substance  must  not  be  mixed  with 
either  mucUage  or  aromatic  bitters,  but  svil- 
phuric  ether  and  cold  water  may  be  joined 
to  it  without  injuring  its  effects. 

-^TiiER  NiTROsus.  —  Swcet  spirit  of 
nitre.  Sweet  spirit  of  niti^e  is  stimulant, 
anti-spasmodic,  diuretic,  and  diaphoretic. 
The  dose  is  from  one  to  two  ounces,  diluted 
with  water. 

Age.  —  The  age  of  a  horse  may  be  known 
by  marks  in  the  front  teeth  and  tusks  of 
the  under  jaw,  until  he  is  about  eight  years 
old,  after  which  period  it  is  a  matter  of 
guess-work  ;  yet  those  who  are  expert  can 
tell  very  near  the  exact  age.  There  are 
many  circumstances  which  tend  to  show 
whether  a  horse  be  old  or  not.  The  num- 
ber of  a  horse's  teeth  is  forty, — twenty-four 
grinders,  and  sixteen  others, —  by  some  of 
which  his  age  may  be  known  up  to  a  certain 
period.  Mares  have  only  thirty-six  teeth, 
as  in  them  the  tushes  are  usually  wanting. 
A  few  days  after  birth,  the  colt  puts  forth 
two  small  front  teeth  in  the  upper  and  un- 
der jaws,  and  soon  after  two  more :  these 
axe  called  nippers.  The  next  four  shortly 
afterwards  make  their  appearance.  The 
four  corner  teeth  —  as  they  are  termed  — 
come  a  few  months  after  the  last  named. 
These  twelve  teeth,  in  the  front  of  the 
mouth,  are  small  and  white,  and  continue 
without  much  alteration  until  the  colt  is 
about  two  years  and  a  half  old,  when  he 
begins  to  shed  them.  The  two  teeth  that 
first  make  their  appearance  are  the  first  that 
are  lost,  and  are  replaced  by  two  others, 
called  horse's  teeth,  considerably  stronger 
and  larger  than  those  that  have  made  way 
for  them.  Between  the  third  and  fourth 
year,  the  two  teeth  next  the  first  fall  out. 


and  are  in  like  manner  replaced  by  horse's 
teeth.  Between  the  fourth  and  fifth  year, 
the  corner  teeth  are  changed ;  the  tushes 
make  their  appearance.  About  the  fifth 
year,  the  horse  is  said  to  have  a  full  mouth. 
After  this  period,  up  to  the  eighth  year,  the 
age  of  a  horse  can,  with  some  degree  of 
certainty,  be  known  by  the  cavities  in  the 
teeth,  which  at  first  are  deep,  but  are  gradu- 
ally, by  the  process  of  mastication,  worn 
down,  and  about  the  eighth  year  disappear. 
After  the  fifth  year,  the  above  criterion  of 
age  may  be  corroborated  by  the  grooves  in 
the  tushes  of  the  male,  which  are  inside ; 
they  are  two  in  number.  At  six,  one  of 
these  cavities,  viz.,  the  one  next  the  grinder, 
disappears ;  at  seven,  the  other  is  consider- 
ably diminished ;  and  at  eight  is  almost, 
but  not  always,  entirely  gone.  After  this 
period,  the  tushes  become  more  blunt  and 
round.  The  marks  in  the  upper  teeth  are 
by  some  considered  indicative  of  the  horse's 
age  ;  those  in  the  two  front  teeth  disappear- 
ing at  eight,  in  the  two  next  at  ten,  and  in 
the  corner  teeth  at  twelve.  The  marks  in 
the  lower  teeth  will  disappear  about  the 
eighth  year. 

As  a  horse  grows  old,  he  generally  turns 
more  or  less  gray ;  the  cavities  above  the 
eyes  become  deeper ;  the  under  lip  falls ; 
the  gums  shrink  away  from  the  teeth,  giving 
them  the  appearance  of  a  greater  length ; 
the  back  becomes  hoUow,  or  curved. 

Age  of  Neat  Cattle  is  known  by  their 
horns.  At  the  age  of  about  two  years, 
they  shed  their  first  fore  teeth,  which  are  re- 
placed by  others,  larger  and  more  prominent ; 
about  five,  the  early  teeth  are  all  replaced 
by  the  permanent  ones.  As  the  animal  ad- 
vances in  years,  these  teeth  wear  down,  the 
enamel  disappears,  and  they  assume  a  black 
or  brown  appearance.  When  three  years 
old,  a  change  takes  place  in  the  structure 
of  the  horns ;  after  which  period  these  ap- 
pendages, like  the  permanent  teeth,  preserve 
the  same  character.  After  the  thnd  year, 
the  horns  continue  to  grow  as  long  as  the 
animal  lives,  and  the  age  is  indicated  by 
the  rings,  or  prominences,  which  are  easily 
distinguished  on  the  horn,  and  by  which  the 


A   DICTIONARY. 


219 


age  of  the  creature  may  be  nearly  ascer- 
tained, by  adding  three  years  to  the  number 
of  rings. 

Airing,  in  the  management  of  horses, 
implies  exercising  them  in  the  open  air. 

Albumen.  —  That  part  of  the  white  of  an 
egg  which  coagulates  into  a  solid  mass 
when  boiled ;  it  abounds  in  the  bones, 
muscles,  cartilage,  hoof,  hair,  etc. 

Alcohol.  —  Rectified  spirit.  This  is  ex- 
tensively used  in  medicine  for  making  tinc- 
tures. With  an  equal  quantity  of  water  it 
is  termed  New  England  rum.  Alcohol  is  a 
powerful  irritant  and  caustic  poison,  to 
whatever  part  of  the  horse  it  is  applied.  If 
applied  externallv,  it  causes  swelling,  pain, 
and  irritation  ;  if  given  internally,  it  absorbs 
from  the  living  parts  the  serous  or  watery 
portion,  and  condenses  the  fibrous  struc- 
ture. Alcohol,  diluted  in  any  form,  acts  on 
the  horse  as  a  diuretic,  causing  the  kidneys 
to  secrete  a  large  amount  of  urine,  in  con- 
sequence of  which  they  become  overworked, 
and  finally  diseased.  It  is  used  as  a  diffu- 
sible stimulant.  The  best  substitute  is 
warm  ginger  tea. 

Aliment.  —  That  which  nourishes  the 
system. 

Alimentary  Canal.  —  The  interior  of 
the  stomach  and  intestines. 

Alkalies.  —  There  are  different  sorts: 
soda,  potash,  and  ammonia,  are  alkalies. 

Aloes. —  Obtained  from  the  aloe  plant. 
The  aloes  now  in  use  as  a  cathartic  for 
horses,  cattle,  and  sheep,  are  the  Barbadoes. 
Pure  Barbadoes  aloes  are  of  a  dark  brown 
color,  present  a  rough  appearance  when 
broken,  and  have  a  rather  pleasant  aroma. 
(See  Purgatives.) 

Alteratives.  —  A  class  of  medicines 
that  act  gradually  and  permanently  upon 
the  horse,  by  increasing  the  tone  and  vigor 
of  the  secreting,  excreting,  and  absorbing 
system,  without  diminishing  or  destroying 
their  power. 

Althea.  —  Marsh  mallows.  This  plant 
is  generally  used  in  the  formation  of  emol- 
lient drinks,  as  it  contains  a  large  amount 
of  mucilage. 


Alum.  —  A  mineral  astringent,  used  to 
destroy  proud  flesh.  "  Alum  is  a  powerful 
astringent,  whether  administered  internally 
or  applied  externally.  It  may  be  given  to 
the  horse  in  doses  of  from  3ij  to  3iv,  and 
its  employment  has  been  attended  with 
some  benefit  in  obstinate  cases  of  diabetes, 
also  in  diarrhoea,  the  primse  viae  having 
been  previously  emptied  by  means  of  lax- 
atives. It  has  Likewise  been  found  useful 
in  dysentery  and  lead  colic.  For  either  of 
these  diseases  it  may  be  advantageously 
conjoined  with  opium  and  aromatics." 
{Mortoti's  Pharmacy.) 

Amaurosis,  or  Gutta  Serena.*  —  This 
disease,  known  by  the  term  glass  eyes^ 
from  the  peculiar  glassy  appearance  the 
organs  assume,  is  generally  considered 
as  dependent  on  a  paralytic  state  of  the 
optic  nerves,  or  of  their  expansions,  the 
retinae.  By  others,  it  is,  however,  thought 
to  arise  from  the  effects  of  inflammation, 
by  which  coagulable  lymph  is  placed  over 
the  optic  nerve,  rendering  the  retina  inac- 
cessible to  the  stimulus  of  light ;  this  can 
hardly  be  an  occasional,  and  is  certainly  not 
the  usual,  cause.  The  disease,  however,  is 
likely  to  arise  from  any  irritation  of  the 
brain ;  thus,  it  is  found  to  follow  staggers 
and  the  loss  of  large  quantities  of  blood; 
which  last-mentioned  cause  especially  af- 
fects the  nervous  system.  The  veterinarian 
should  make  himself  familiar  with  the  ap- 
pearances of  this  complaint,  otherwise  he 
may  lie  open  to  serious  imposition.  In 
amaurosis,  a  horse  presents  indications  of 
blindness  in  his  manner,  though  but  little  in 
his  eyes ;  he  seems  cautious  in  stepping ; 
lifts  his  legs  high,  and  moves  his  ears 
quickly,  as  though  endeavoring  to  make  up 
by  sound  the  intelligence  lost  by  the  depri- 
vation of  sight :  but,  above  all,  a  hand 
moved  close  to  the  eye  occasions  no  wink- 
ing, unless  held  near  enough  for  the  motion 
to  influence  the  ah-  around,  which  an  artful 
person  might  manage  with  ease.  When 
this  Idnd  of  eye  is  examined  closely,  the 
pupil  will  be  found  of  one  invariable  size 

*  Blaine. 


220 


A   DICTIONARY. 


and  unvarying  hue  ;  it  will  not  enlarge  and 
diminish  as  in  a  healthy  horse,  when  re- 
moved farther  from,  or  nearer  to,  the  light ; 
for  the  retina,  ceasing  to  be  influenced  by 
the  luminous  ray,  no  longer  controls  the 
movements  of  the  iris.  It  is,  therefore,  from 
the  peculiarities  in  the  manner  of  the  horse, 
the  invariable  size  of  the  pupil,  and  a  green- 
ish glassy  cast  in  such  eyes,  that  these  cases 
may  be  distinguished.  As  it  has  hitherto 
proved  incurable,  we  shall  waste  no  time  on 
its  treatment. 

Ammonia.  —  This  is  a  volatile  alkali ;  is 
rapidly  absorbed  by  water ;  and,  by  union 
with  acids,  forms  several  salts.  The  com- 
pounds of  ammonia  employed  medicinally 
are:  hydrochlorate  of  ammonia,  sesqui-car- 
bonate,  and  solution  of  the  acetate  of 
ammonia.  The  aromatic  spirit  of  ammonia 
is  a  valuable  stimulant  and  anti-spasmodic 
in  colic  or  hoven.  For  the  preparation  of 
the  latter,  I\Ir.  Morton  gives  the  following 
formula : 

Talic  of  spirit  of  ammonia,  8  fluid  ounces ;  volatile 
oil  of  lemons,  1  fluid  drachm  ;  volatile  oil  of  rosemary, 
1^  fluid  drachm.  Dissolve  the  oil  in  the  sjm-it  by 
agitation. 

Anasarca.  —  That  form  of  dropsy  that 
affects  the  whole,  or  nearly  the  whole  sys- 
tem, or,  in  other  words,  an  effusion  of  serum 
into  the  meshes  of  the  cellular  tissue. 

Anasarca,  CEdema,and  Water  Farcy.* 
—  "We  need  make  no  distinction  between 
these  terms,  particularly  the  two  fii'st.  As 
generally  accepted,  oedema  carries  probably 
rather  a  more  local  definition  with  it ;  thus, 
we  say  an  cedematous  swelling :  but  ana- 
sarca is  more  frequently  used  to  designate 
an  extensive  dropsy  of  tlie  cellular  mem- 
brane. Both,  however,  have  the  same 
origin,  and  are  accompanied  by  the  same 
symptoms.  It  differs  from  ascites  princi- 
pally in  its  external  seat,  which  is  some- 
times partial  and  sometimes  general.  It 
also  appears  under  different  forms,  as  it  has 
different  origins ;  and  its  terminations  are 
also  under  the  influence  of  these  ckcum- 
stances.    A  debility  of  the  absorbent  system 

*  Blaine. 


is  usually  observed  in  the  spring  and  au- 
tumn. There  is,  however,  some  general 
atony  of  the  whole  system,  and  the  oedema 
disappears  as  the  constitution  establishes 
itself.  At  other  times  anasarca  and  oedema 
appear  as  accompaniments  or  sequelae  to 
acute  diseases  that  have  disturbed  the  func- 
tions generally,  in  the  which  case  the 
absorbents  become  irritated ;  or  to  the 
oedema  is  added  tumefied  lymphatics. 

ANiESTHETics. —  Agcuts  which  produce 
insensibility  to  external  impressions  and  to 
pain.  The  author  uses,  for  inhalation,  three 
parts  of  sulphuric  ether  to  one  of  chloroform. 
In  allusion  to  the  use  of  anaesthetics, 
Mr.  Morton  wi-ites :  "  Anaesthetics  are  less 
used  in  surgical  and  other  painful  operations 
in  the  lower  animals  than  in  man,  on  account 
of  the  larger  quantities  required,  the  diffi- 
culty of  administration,  and  the  undue  pro- 
longation of  the  preliminary  stage  of 
excitement.  They  have  been  used  in  par- 
turition, and  afford,  as  in  the  human  subject, 
immunity  from  pain,  but  without  apparent 
interference  with  the  force  or  frequency  of 
the  involuntary  contractions  of  the  uterus. 
They  have  fiuther  been  used  for  relieving 
the  irritability  and  pain  of  such  diseases  as 
peritonitis,  pleurisy,  and  pneumonia ;  for 
removing  the  spasms  of  tetanus,  colic,  and 
asthma  ;  and  for  alleviating,  by  local  appli- 
cation, the  irritability  of  severe  wounds. 
For  all  such  purposes  their  use  might,  with 
advantage,  be  much  extended." 

Anastomosis.  —  The  communication  of 
blood-vessels  with  each  other,  or  their  open- 
ing one  into  the  other,  by  which  means, 
when  the  passage  of  blood  through  an 
artery  or  vein  is  prevented  by  ligatm*e,  com- 
pression, or  any  other  cause,  the  circulation 
is  still  kept  up  by  means  of  the  anastom- 
osing vessels. 

Anatomy. —  The  science  that  teaches 
the  structure  of  the  animal  economy. 

Analysis.  —  The  resolution  of  compound 
bodies  into  their  original  or  constituent  prin- 
ciples. 

Anchylosis.  —  The  loss  of  motion  in  a 
joint.     There  are  two  kinds,  caUed  com- 


A   DICTIONARY. 


221 


plete  and  incomplete.  In  the  former,  the 
joint  has  grown  together  so  as  to  be  immov- 
able ;  in  the  latter,  some  motion  remains, 
and  the  rigidity  is  owing  to  the  contraction 
and  thickening  of  the  ligaments.  Anchy- 
losis in  the  horse  is  not  unfrequently  a  con- 
sequence of  wounds  or  bruises  ;  the  latter, 
causing  an  absorption  of  the  fluids  that 
nourish  the  joint,  anchylosis  is  the  result. 
In  bad  spavins  and  ringbones,  there  is  fre- 
quently anchylosis  of  the  hock  and  pastern 
joints.  The  author's  attention  has  lately 
been  called  to  a  case  of  ringbone  that  had 
been  operated  upon  by  some  person  totally 
unacquainted  with  the  nature  of  the  disease. 
The  operation  was  performed  in  the  most 
cruel  and  barbarous  manner.  The  operator 
having  never  studied  the  anatomy  of  the 
parts,  it  could  not  be  otherwise  expected. 
On  an  examination  of  the  animal,  ossific 
or  bony  deposits  were  found  inside  the  hind 
legs,  in  the  form  of  a  spavin ;  deposits  also 
existed  on  the  canon  bones,  and  on  the 
pasterns,  thus  proving  that  the  disease  was 
incurable ;  the  general  health  was  impaired, 
the  knees  sprung,  and  the  animal  was  pro- 
nounced by  the  owner  to  be  worthless  ;  yet 
this  specimen  of  inhumanity,  the  self-styled 
"  doctor,"  had  the  audacity  to  state  that  he 
could  perform  a  cure  for  the  trifling  sum  of 
five  dollars;  The  fact  of  his  attempting  to 
cure  a  constitutional  disease  by  local  means, 
under  such  unfavorable  circumstances, 
shows  that  he  was  an  ignoramus  ;  and  the 
barbarous  manner  in  which  he  performed 
the  operation,  shows  that  he  was  destitute 
of  every  particle  of  humanity.  The  author 
has  digressed  merely  for  the  purpose  of 
warning  owners  of  domestic  animals 
against  trusting  them,  when  diseased,  in 
the  hands  of  those  who  are  unacquainted 
with  their  mechanism. 

Aneurism.  —  A  tumor  filled  with  blood, 
communicating  with  an  artery.  It  usually 
occurs  from  rupture  of  one  of  the  coats  of 
the  artery,  and  dilitation  of  the  cellular  coat: 
it  is  then  denominated  true  aneurism. 
When  an  artery  is  wounded,  and  the  blood 
escapes  into  the  surrounding  tissues,  it  is 
called  false  aneurism. 


The  general  mode  of  curing  aneurism  is 
by  tying  a  ligature  around  the  artery ;  the 
coats  of  the  ^artery  become  united,  and  part 
of  the  artery  obliterated  ;  the  circulation  is 
carried  on  by  anastomosing  vessels.  (See 
Anastomosis.)  Some  aneurisms  have  been 
known  to  undergo  certain  natural  changes, 
by  which  they  have  been  spontaneously 
cured,  thus  proving  that  the  vital  power  is 
more  efficient  "  than  an  evil  system  of  med- 
ication." 

Anise  Seed. —  A  mild  carminative.  It 
is  much  used  in  veterinary  practice,  and  is 
one  of  the  ingredients  in  cordial  balls. 

Anodynes. —  Medicines  that  relieve  pain, 
procure  sleep,  and  lessen  the  irritability  of 
the  nervous  system. 


antacids. 


ALKALIES. 


Anthelmintics. — Medicines  that  are  said 
to  destroy  worms,  and  are  supposed  to  cause 
their  expulsion  from  the  animal.  Many  of 
the  remedies  recommended  by  some  writers 
would  be  more  likely  to  kill  the  horse,  in- 
stead of  the  former.  The  proper  method 
of  preventing  the  generation  of  worms  in 
the  alimentary  canal,  is  to  pay  attention  to 
feeding,  watering,  etc.,  and  give  cathartics. 

Antimony. —  A  mineral  poison.  It  has 
been  extensively  used  in  veterinary  practice. 
There  are  numerous  preparations  of  anti- 
mony, but  they  are  all  more  or  less  objec- 
tionable. Large  quantities  of  this  mineral 
have  been  used  on  horses ;  yet,  in  some 
cases,  where  there  is  vital  power  enough  in 
the  animal  to  dispossess  it  from  the  system, 
no  immediately  unfavorable  results  were 
observed.  Yet  it  is  an  agent  of  such  diver- 
sified therapeutical  powers,  that  the  wisest 
of  the  faculty  have  never  ventured  to  pre- 
scribe and  fix  limits  to  its  action.     (See 

TOXICOLOGICAL    ChaRT.) 

Mr.  Finlay  Dun,  of  the  Edinburgh  college, 
has  lately  made  a  series  of  experiments 
with  tartar  emetic,  on  horses,  and  he  speaks 
very  highly  of  it  as  antiphlogistic.  The 
dose  for  a  horse  is  from  one  to  four  drachms, 
either  in  bolus  or  solution,  repeated  as  oc- 
casion may  require. 

Antidotes. — See  Toxicological  Chart. 


222 


A   DICTIONARY, 


Antiseptics. —  Medicines  that  correct 
and  prevent  puti-idity.  The  best  and  most 
efficient  are  charcoal,  Peruvian  bark,  acetic 
acid,  and  bayberry  bark. 

Anti-spasmodics. —  Medicines  that  are 
employed  in  spasmodic  and  convulsive  dis- 
orders. The  most  efficient  are  assafoetida, 
pennyroyal,  or  any  of  the  mints.  The  most 
powerful  in  spasm,  or  lockjaw,  are  lobelia, 
warmth  and  moisture,  castor,  musk,  gin- 
seng, and  Indian  hemp,  or  milk  weed. 

Apoplexy.  —  A  lesion  of  some  of  the 
vessels  of  the  brain. 

Arm.  —  A  term  applied  to  the  upper  part 
of  the  fore  leg. 

Aromatics.  —  Medicines  that  have  a 
warm,  pungent  taste,  and  fragrant  smell ; 
of  this  kind  are  cardamom  seeds,  cloves, 
and  nutmegs,  sweet  flag,  etc. 

Arsenic  —  A  destructive  mineral  poison. 
It  has  been  used,  in  many  diseases  of  the 
horse,  without  the  slightest  benefit.  Dr. 
White  states,  "  So  various  are  its  effects, 
that  he  has  known  a  very  small  quantity  to 
terminate  fatally." 

Arteriotomy.  —  When  blood  is  taken 
from  an  artery,  the  process  is  called  arteri- 
otomy. The  proper  place  for  puncturing 
the  temporal  artery,  is  at  the  precise  spot 
where  this  vessel  leaves  the  parotid  gland 
to  curve  upwards  and  forwards  around  the 
jaw,  which  is  just  below  its  condyle.  The 
operation  should  be  performed  with  a  lan- 
cet. 

Arterio  -  Phlebotomy  is  sometimes  re- 
sorted to  for  the  abstracting  blood  from 
the  roof  of  the  mouth  and  the  toe  of  the 
foot ;  in  such  cases,  however,  a  want  of 
knowledge,  as  regards  the  anatomy  of  the 
parts,  may  occasion  a  serious  haemorrhage. 

Ascites.  —  Dropsy  of  the  abdomen. 

Asthma.  —  Supposed  to  originate  in  the 
muscles  of  respiration.  (See  Cough,  Roar- 
ing, etc.) 

Astringents.  —  Medicines  that  contract 
and  condense  muscular  fibre.  The  princi- 
pal are  kino,  catechu,  oak  bark,  nutgalls, 
and  bayberry  bark. 

Atmosphere.  —  The  name  given  to  an 
elastic  invisible  fluid  which  surrounds  the 


globe ;  it  is  composed  of  oxygen,  nitrogen, 
and  a  small  portion  of  carbonic  acid  gas. 
In  stables  that  are  not  ventilated,  the  vapor 
arising  from  the  dung  and  urine  combine 
with  it,  and  render  it  unfit  for  respiration. 

Atlas.  —  The  first  vertebra,  or  bone  of 
the  neck. 

Atrophy.  —  A  wasting  of  the  body. 

Auricles.  —  The  two  small  cavities  of 
the  heart. 

Backgalled.  —  When  accidents  of  this 
kind  occur,  the  saddle  or  harness  should  be 
padded,  or  chambered,  so  as  to  remove 
pressure  from  the  part ;  sometimes  they  are 
difficult  to  heal,  owing  to  the  presence  of 
morbific  matter  in  the  system. 

Backraking.  —  This  is  a  name  given  by 
farriers  to  the  operation  of  introducing  the 
hand  into  the  fundament,  and  emptying  the 
rectum  of  its  contents.  The  use  of  injec- 
tions wdll,  ere  long,  supersede  this  beastly 
practice.  The  most  suitable  injection  to 
soften  the  fseces  is  warm  soapsuds. 

Back  Sinews.  —  The  flexor  tendons  of 
the  fore  and  hind  legs  are  so  named.  They 
are  frequently  strained,  or  otherwise  injured, 
by  over  exertion  or  accidents. 

Ball.  —  Bolus,  or  large  pill.  The  mode 
of  giving  a  ball  is  by  drawing  out  the 
tongue  to  the  right  side,  and  holding  it  in 
the  left  hand,  while  an  assistant  stands  on 
the  left  side  and  holds  the  mouth  open. 
The  ball  is  to  be  held  by  the  finger  and 
thumb  of  the  right  hand,  di-awn  into  as 
small  a  compass  as  possible,  and  passed  as 
far  as  the  horse's  throat.  This  must  be 
done  by  a  quick  motion  of  the  hand,  which 
should  be  kept  toward  the  roof  of  the 
mouth,  as  there  is  more  room  for  it  in  that 
direction. 

Balsam. —  A  name  applied  to  several 
resinous  substances,  such  as  balsam  of  tolu, 
Peruvian  balsam,  balsam  copaiba,  etc., 
Canada  or  fir  balsam  ;  the  medicinal  prop- 
erties are  stimulant  and  diuretic. 

Balsam  Copaiba,  or  Capivi,  is  used  for 
chronic  cough  ;  the  dose  is  about  one  ounce. 

Balsam  of  Sulphur. —  A  preparation 
made  by  boiling  sulphur  and  olive  oil  to- 
gether, until  united  in  the  form  of  a  dark- 


A  DICTIONARY. 


223 


colored  tenacious  mass.  This  has  been 
much  esteemed  by  old  farriers  in  obstinate 
coughs.  When  mixed  with  a  small  propor- 
tion of  oil  of  anise-seed,  it  has  been  thought 
more  efficacious,  and  is  then  named  anis- 
ated  balsam  of  sulphur. 

Bandage.  — ■  Strips  of  linen,  cotton,  or 
flannel,  about  three  or  four  inches  wide. 
They  are  serviceable  in  habitual  swellings 
of  the  legs,  or  weakness  of  the  fetlock  joint. 
They  are  likewise  used  for  the  purpose  of 
keeping  on  dressings,  or  assisting  in  uniting 
parts  that  are  cut  or  lacerated  ;  they  assist 
by  pressm-e  in  expelling  matter,  or  pre- 
venting the  descent  of  ruptures,  and  as 
compresses  for  restraining  bleeding  or  hem- 
on-hage.  The  mode  of  applying  the  bandage 
to  the  leg  is  as  follows  :  the  material,  after 
being  cut  the  proper  width,  must  be  rolled 
up,  and  the  bandage  fixed  by  taking  two  or 
three  turns  in  the  same  place  ;  after  which, 
the  roller  may  be  carried  round  spirally, 
taking  care  that  every  turn  of  the  bandage 
overlaps  about  two-thirds  of  the  preceding 
one.  When  the  inequality  of  the  parts 
cause  the  margin  to  slack,  it  must  be  re- 
versed, or  folded  over;  that  is,  its  upper 
margin  must  become  the  lower,  etc.  A 
bandage  should  be  moderately  tight,  so  as 
to  support  the  parts  without  intercepting 
the  circulation,  and  should  be  so  applied  as 
to  press  equally  on  every  part.  In  band- 
aging a  horse's  leg,  the  roller  should  be 
applied  from  the  upper  part  of  the  hoof  to 
the  knee ;  in  every  case  it  is  advisable  to 
bandage  from  joint  to  joint,  thus  leaving 
the  joint  at  liberty.  When  it  is  found 
necessary  to  bandage  a  joint,  the  bandage 
should  be  put  on  in  the  form  of  a  figure  8. 

Barb.  —  A  general  name  for  horses  im- 
ported from  Barbary.  The  barb,  one  of 
the  most  celebrated  of  the  African  races,  is 
to  be  met  with  in  Barbary,  Tripoli,  and 
Morocco  ;  he  seldom  exceeds  more  than  four- 
teen hands  and  a  half  in  height.  The  barb 
requires  more  excitement  to  call  out  his 
powers  than  the  Arabian  ;  but,  when  suf- 
ficiently excited,  his  qualities  of  speed  and 
endurance  render  him  a  powerful  antagonist 
to  the  Arabian. 


Bark.  —  This  name  is  generally  applied 
to  several  different  species  of  Peruvian 
bark,  the  yellow  and  the  red.  The  active 
principle  of  the  yellow  bark  is  an  alkaloid 
principle,  called  quinse,  combine-d  with  a 
peculiar  acid,  called  Idnic,  or  cinchonic,  in 
the  state  of  an  acid  salt ;  besides  these,  it 
contains  an  oily  and  a  yellow  coloring  mat- 
ter, tannin,  kinate  of  lime,  and  woody  fibre. 
Their  value  in  treating  diseases  of  the  horse 
consists  in  their  tonic  and  astringent  prop- 
erties. It  should  be  given  to  the  horse  in 
the  form  of  infusion;  one  ounce  of  pow- 
dered bark  to  a  quart  of  boiling  water.  It 
is  also  useful  to  restore  indolent  ulcers  to  a 
healthy  state.  The  best  tonic  for  a  horse  is 
hydrastis  Canadensis  (golden  seal). 

Bar  Shoe.  —  A  particular  kind  of  shoe, 
which  is  sometimes  used  to  protect  the  frog 
from  injury;  also  in  corns. 

Bars  of  the  Foot. —  (See  Foot,  part 
first.) 

Bars  of  the  Mouth.  —  Transverse  ridges 
on  the  roof  of  the  mouth ;  they  are  most 
conspicuous,  or  full,  in  a  young  horse. 
When  swollen,  or  fuller  than  usual,  the 
horse  is  said  to  have  the  lampas. 

Basilicon. —  A  digestive  ointment,  com- 
posed of  equal  parts  of  olive  oil,  yellow 
beeswax,  and  common  resin  (or  rosin). 
These  are  to  be  melted  over  a  slow  fire, 
and  stirred  until  the  mixture  is  quite  cool. 

Bay.  —  A  bay  color,  in  horses,  is  so 
named  from  its  resemblance  to  dried  bay 
leaves. 

Biceps.  —  The  biceps  is  a  double-headed 
muscle,  which  serves  to  bend  a  limb. 

Bile,  or  Gall.  —  A  bitter,  greenish  fluid, 
secreted  by  the  liver  for  the  purpose  of  as- 
sisting digestion.  In  the  horse  there  is  no 
gall  bladder,  or  receptacle  for  the  bile ;  it 
passes  directly  into  the  duodenum,  or  fii'st 
part  of  the  small  intestines,  a  few  inches 
from  the  stomach. 

Bilious.  —  Diseases  are  called  bilious 
when  they  depend  on  a  morbid  state  of  the 
liver. 

Bits. —  There  are  various  kinds  of  bits 
in  use  ;  among  them  are  the  snaffle  and 
curb.     A   snaffle   may  be  either  plain,  or 


224 


A   DICTIONARY. 


twisted,  but  the  latter  is  apt  to  make  the 
mouth  callous ;  it  consists  of  two  pieces, 
having  a  sort  of  hinge  joint  in  the  centre. 
When  used  for  the  purpose  of  breaking 
young  colts,  it  should  be  made  large,  so  as 
not  to  hurt  the  mouth.  The  form  of  the 
curb  bit  resembles  somewhat  the  letter  H. 
The  bridle  is  fastened  to  the  side  pieces, 
which  act  as  levers  of  different  powers,  ac- 
cording to  the  distance  from  the  cross-bar, 
to  which  the  bridle  is  attached.  The  hu- 
mane man  will  never  inflict  unnecessary 
severity  on  the  horse,  and  will  avoid  contin- 
ual strain  on  the  reins  or  bridle,  which, 
aside  from  the  torture  they  inflict,  tend  to 
render  the  horse's  mouth  callous.  The  best 
form  of  bit,  and  the  most  simple,  is  the  stiff, 
arched  bit.  The  author  has  seen  a  very  fine 
specimen  of  this  article,  manufactm-ed  by 
Messrs.  Hannaford  &  Hsley,  of  this  city. 
The  centre  piece  is  large  and  curved ;  the 
checks  are  movable,  and  their  upper  ends 
curved  outwards,  which  prevents  their  injur- 
ing the  cheek  bones.  It  is  very  important 
that  a  horse  should  be  properly  bitted; 
many  docile  horses  are  rendered  stubborn 
and  unmanageable,  by  having  a  bit  that  is 
too  narrow.  INIany  young  horses  are  injm-ed 
while  they  are  teething,  and  the  mouth  is 
tender,  by  bearing  too  hard  on  the  rein. 
The  author  would  suggest  a  tiial  of  an 
Lidia  rubber  centre  piece,  in  such  cases. 

Bite  of  any  Rabid  Animal.  —  In  most 
works  on  veterinary  science,  the  writers  re- 
commend excision,  or  cutting  out  the  bitten 
part,  and  afterwards  cauterizing  with  the 
firing  iron  ;  but  this  method  is  very  unsatis- 
factory, and  only  puts  the  animal  to  unne- 
cessary torment.  The  morbid  matter  from 
a  rabid  animal  is  generally  taken  up  by  the 
absorbents,  sometimes  in  a  few  seconds, 
and  the  operation  of  cauterizing  would  then 
be  of  no  avail.  The  treatment  we  recom- 
mend is,  to  dose  the  animal  with  a  tea  of 
lobelia ;  half  a  pound  of  the  herb  and  seed 
may  be  steeped  in  two  quarts  of  scalding 
water,  and  given  in  doses  of  half  a  pint,  at 
intervals  of  an  hour.  A  large  poultice  of 
the  same  should  be  bound  on  the  bitten 
part,  and  kept  in  contact  with  the  parts  by 


bandages,  and  the  poultice  renewed  every 
six  hours,  until  all  signs  of  poisoning  disap- 
pear. The  animal  should  be  kept  on  scalded 
shorts,  in  moderate  quantities. 

Bladder. —  The  bladder  is  a  musculo- 
membranous  bag,  situated,  when  empty,  in 
the  cavity  of  the  pelvis.  Its  use  is  to  con- 
tain the  urine,  which  flows  into  it  through 
the  m'eters,  from  the  kidneys.  It  is  divided 
into  three  parts,  viz.,  the  fundus  or  bottom, 
the  body,  and  the  neck.  When  full,  the 
fundus  of  the  bladder  protrudes  out  of  the 
pelvis,  into  the  abdominal  cavity ;  it  then 
receives  a  covering  from  the  peritoneum. 
Its  other  coats  are  an  internal  mucous  mem- 
brane, and  an  external  muscular  coat,  formed 
of  two  distinct  sets  of  fibres ;  the  one  lon- 
gitudinal, and  the  other  circular.  The 
former  are  thickest  about  the  fundus,  the 
latter  about  the  neck  or  cervix,  —  which,  by 
this  arrangement,  is  always  kept  closed, 
except  dm-ing  the  time  of  voiding  the  mine. 
On  opening  horses  that  have  died  from 
accident,  we  sometimes  find  the  bladder 
empty,  and  its  muscular  fibres  so  condensed 
that  it  appears  like  a  solid  mass  of  small 
dimensions  ;  such  is  the  contractile  power 
of  its  muscular  coat,  by  which,  with  some 
assistance  from  the  abdominal  muscles  and 
diaphragm,  the  urine  is  expelled.  The 
author  has  opened  several  horses  that  have 
died  from  lockjaw,  and  found  the  bladder 
distended  to  its  utmost  capacity,  containing 
about  a  gallon  and  a  half  of  dark-colored 
fluid,  resembling  coffee-grounds.  In  one 
case,  the  muscular  fibres  about  the  neck 
of  the  bladder  were  lacerated  by  the  over- 
distention  and  spasm  of  the  neck  of  that 
organ.  When  horses  are  accustomed  to 
drink  too  much  water,  without  being  al- 
lowed to  stale  often  enough  at  work,  the 
bladder  becomes  over-distended,  and  often 
paralysis,  weakness,  or  local  debility  sets 
in,  and  the  neck  of  the  bladder  becomes  at 
length  so  relaxed  as  to  be  unable  to  offer 
sufficient  resistance  to  the  muscles  that  pro- 
pel the  urine  into  the  urethra,  so  that  it  is 
constantly  dribbling  off  as  fast  as  it  is 
secreted.  This  is  termed  incontinence  of 
mine. 


A   DICTIONARY. 


225 


Sometimes  the  irritability  of  the  bladder, 
in  the  latter  case,  depends  on  the  acrimony 
of  the  urine  ;  and,  whenever  this  is  the  case, 
attention  to  feeding,  watering,  etc.,  will 
remove  it.  Diseases  of  the  kidneys  and 
bladder  are  accompanied  with  tenderness 
over  the  loins,  and  a  remarkable  stiffness  of 
the  hind  legs.  Whenever  the  bladder  is 
distended  with  urine,  recourse  should  be 
had  to  the  catheter. 

Palsy,  or  paralysis,  of  the  bladder,  is 
sometimes  dependent  on  functional  de- 
rangements, as  stomach  staggers,  or  injuries 
to  the  brain  and  spinal  marrow.  . 

Blasting.  —  When  cattle  or  sheep  are 
first  turned  into  luxuriant  pasture,  after  be- 
ing poorly  fed,  they  frequently  gorge  them- 
selves with  food,  which,  fermenting  in  the 
rumen,  or  paunch,  so  distends  it  with  gas 
that  the  animal  is  often  in  danger  of  suffo- 
cation. The  symptoms  are  most  distressing; 
and,  unless  relief  be  speedily  afforded,  death 
very  commonly  ensues.  If  the  symptoms 
are  very  alarming,  a  flexible  tube  may  be 
passed  down  the  gullet :  this  will  generally 
allow  the  gas  to  escape,  and  afford  tempo- 
rary relief,  until  more  efficient  means  are 
resorted  to  ;  these  will  consist  in  arousing 
the  stomach  and  digestive  organs  to  action, 
by  stimulants  and  carminatives,  and  coun- 
teracting the  tendency  to  putrescence  by 
doses  of  charcoal  or  lobelia.  Some  prac- 
titioners recommend  puncturing  the  rumen, 
or  paunch  ;  but  there  is  always  great  dan- 
ger attending  it,  and,  at  best,  it  is  only 
palliative,  and  the  process  of  fermentation 
will  proceed  ;  the  gas  may  escape,  but  the 
materials  that  furnished  it  still  remain. 
Youatt  states  :  "  A  cow  had  eaten  a  large 
quantity  of  food,  and  was  hoven.  A  neigh- 
bor, who  was  supposed  to  know  a  great 
deal  about  cattle,  made  an  incision  into  the 
paunch  ;  the  gas  escaped,  a  great  portion 
of  the  food  was  removed  with  the  hand, 
and  the  animal  appeared  to  be  considerably 
relieved,  but  rumination  did  not  return  :  on 
the  following  day  the  animal  was  dull ;  she 
refused  her  food,  but  was  eager  to  drink. 
She  became  worse  and  worse,  and  on  the 

29 


sixth  day  she  died;"  thus  proving  that  the 
remedy  was  worse  than  the  disease. 

When  animals  are  blasted  in  a  moderate 
degree,  the  carminative  drink,  and  decoction 
of  lobelia,  will  prove  effectual.  In  all  cases 
of  hove,  it  will  be  advisable  to  give  injec- 
tions of  warm  water,  to  which  add  a  hand- 
ful of  salt,  and  the  same  quantity  of 
charcoal.  As  a  means  of  preventing  the 
blast,  it  may  be  remarlced,  that  animals 
should  never  be  turned  into  any  nutritive 
pasture  while  the  dew  is  on  the  ground,  or 
after  rain. 

Bleeding. —  The  practice  of  abstracting 
blood  has  received  the  seal  of  antiquity,  yet 
that  is  no  argument  in  favor  of  its  useful- 
ness ;  and,  in  view  of  improving  in  the 
future,  the  author  here  introduces  an  article 
on  the  subject,  by  Professor  Buchanan  : 

"  We  affirm  that  bleeding  is  a  barbarous 
and  unscientific  remedy,  and  deny  that  it  is 
ever  necessary.  In  this  matter  we  take  our 
stand  upon  the  facts  recognized  by  the  high- 
est authorities  in  medical  fiterature.  We 
refer  to  the  most  recent  and  accurate  re- 
searches in  chemistry  and  pathology  ;  to  the 
experimental  investigations  of  Andral,  Ma- 
gendie,  Louis,  Simon,  and  many  others, 
which  have  settled,  beyond  all  doubt,  and 
placed  among  the  permanent  facts  of  medi- 
cal science,  to  be  received  by  all  medical 
schools  of  whatever  therapeutic  faith,  the 
phenomena  of  the  blood,  when  its  composi- 
tion has  been  affected  by  hemorrhage,  by 
bleeding,  and  by  various  other  agencies. 

"  It  is  indisputably  established  that  bleed- 
ing produces  a  special  change  in  the  com- 
position of  the  blood.  The  change  which 
it  produces  is  not  a  removal  of  any  effete  or 
morbid  materials, — not  a  removal  of  any 
element  which  tends  to  create  or  aggravate 
disease,  —  but  a  removal  of  the  most  neces- 
sary and  healthy  portion,  upon  the  presence 
of  which  we  depend  for  the  maintenance  of 
health  and  vigor.  Bleeding  inevitably  re- 
duces the  red  or  globulous  portion  of  the 
blood,  because  it  removes  or  destroys  a 
certain  amount  of  the  red  globules,  and  the 
loss  which  it  produces  is  readily  supplied  by 


226 


A    DICTIONARY. 


absorption  of  water  and  of  comparatively 
crude  materials,  while  the  highly-organized 
globules  are  regenerated  with  great  slow- 
ness and  difficulty. 

"  It  is  a  well-established  fact,  that  the  red 
globules  of  the  blood  are  essential  to  life, 
and  that  their  abundance  or  scarcity  is  a 
criterion  of  the  vital  force  and  activity  of 
the  constitution.  As  the  proportion  of  the 
red  globules  increases,  the  general  vital 
power  rises,  and  the  activity  or  energy  of  all 
the  organs  increases  ;  while  a  diminution  of 
their  ratio  enfeebles  or  disorders  the  various 
organs,  and  predisposes  to  nervous  and 
tuberculous  disorders,  and  to  the  whole 
range  of  adynamic  and  cachectic  diseases. 
If  the  ratio  is  diminished  as  much  as  one- 
seventh,  general  debility  is  the  consequence, 
predisposing  to  disease  and  diminishing  the 
power  of  recovery  ;  if  as  much  as  one-fourth 
or  more,  this  reduction  of  vital  power  is 
incompatible  with  health,  and  inevitably 
results  in  some  form  of  disorder. 

"  Is  it  not,  then,  exquisitely  absurd  to 
adopt,  as  a  remedy  in  disease,  a  measure 
which,  even  in  the  most  vigorous  health, 
tends  directly,  with  rigorous  precision,  to 
destroy  the  vital  powers  and  bring  on 
disease  ?  Yet  this  measure  has  been,  and 
still  is,  sustained  by  many  medical  men, 
although  clinical  experience,  as  w^ell  as 
chemical  science,  has  shown  its  injurious 
effects,  and  thousands  in  America  and 
Europe  have  been,  and  are  now,  demon- 
strating that  all  forms  of  disease  may  be 
better  treated  without  bloodletting  than 
with  it. 

"  We  affirm  that,  in  disease,  the  patho- 
genetic elements  of  the  blood  should  be 
removed,  instead  of  its  healthful  and  neces- 
sary constituents.  Nature  has  provided  for 
the  removal  of  all  noxious  materials,  by 
numerous  appropriate  outlets,  which  dis- 
charge every  thingthat  is  injurious  to  human 
health.  It  is  the  duty  of  the  physician  to 
aid  nature  by  such  medicines  and  means  as 
will  rouse  the  secretions  and  excretions,  and 
thus  insm-e  the  restoration  of  the  blood  to  a 
perfectly  healthy  condition.  When,  for 
want  of  knowledge  how  to  accomplish  this, 


he  destroys  with  unnatural  violence  a  large 
portion  of  the  vital  blood  itself,  which  is  as 
necessary  to  the  body  as  its  solid  tissues,  he 
acts  with  as  much  scientific  precision  as  the 
savage,  who  would  treat  a  case  of  convul- 
sions, not  by  removing  its  causes,  but  by 
cutting  out  a  portion  of  the  convulsed 
muscles." 

It  will  be  very  difficult,  however,  to  con- 
vince some  of  the  "  older  heads^^  and  the 
world  in  general,  that  bleeding  can  be  dis- 
pensed with  ;  therefore  the  veterinarian  must 
be  prepared  to  please  his  employer,  and  do 
just  as  his  superiors  have  done,  —  or  else 
"  loose  caste  "  and  practice. 

Blemishes.  —  They  consist  of  broken 
knees,  loss  of  hair,  cracked  heels,  false  quar- 
ters, splents,  windgalls,  spavins,  etc. 

Blind,  Moon.  —  A  disease  of  the  horse's 
eyes,  which  is  supposed  to  be  the  forerunner 
of  cataract,  and  often  ends  in  total  blindness. 

Blister  Fly. —  Cantharides,  or  Spanish 
fly.  The  object  in  applying  a  blister  is  to 
promote  absortions  and  to  combat  deep- 
seated  inflammations. 

Bloodroot.  —  Sanguinaria  Canadensis, 
used  to  prevent  the  growth  of  fungus,  or 
proud  flesh  ;  a  substitute  for  caustic. 

Blood  Spavin. —  Enlarged  bursas. 

BoTs. — Short  reddish  worms,  which  are 
often  found  attached  to  the  horse's  stomach. 
Mr.  Clark  says  "  that  bots  are  not,  properly 
speaking,  worms,  but  the  larvae  of  the  gad- 
fly, which  deposits  its  eggs  on  the  horse's 
coat  in  such  a  manner  as  that  they  shall  be 
received  into  his  stomach,  and  then  become 
bots.  When  the  female  fly  has  become  im- 
pregnated, and  the  eggs  are  sufficiently  ma- 
tured, she  seeks  among  the  horses  a  subject 
for  her  pm-pose,  and,  approaching  it  on  the 
wing,  she  holds  her  body  nearly  upright  in 
the  air,  and  her  tail,  which  is  lengthened  for 
the  purpose,  carried  inwards  and  upwards. 
In  this  way  she  approaches  the  part  where 
she  designs  to  deposit  the  eggs ;  and,  sus- 
pending herself  for  a  few  seconds  before  it, 
suddenly  darts  upon  it,  and  leaves  the  egg 
adhering  to  the  hair  by  means  of  a  gluti- 
nous liquor  secreted  with  it.  She  then 
leaves  the  horse  at  a  small  distance,  and  pre- 


A   DICTIONARY. 


227 


pares  the  second  egg ;  and,  poising  herself 
before  the  part,  deposits  it  in  the  same  way  ; 
the  liquor  dries,  and  the  egg  becomes  firmly 
glued  to  the  hair.  This  is  repeated  by  va- 
rious flies,  till  four  or  five  hundred  eggs  are 
sometimes  deposited  on  one  horse.  They 
are  usually  deposited  on  the  legs,  side,  and 
back  of  the  shoulder,  —  those  parts  most  ex- 
posed to  be  licked  by  the  animal :  in  lick- 
ing, the  eggs  adhere  to  the  tongue,  and  are 
carried  into  the  horse's  stomach  in  the  act 
of  sv^allowing.  The  bots  attach  them- 
selves to  the  horse's  stomach,  and  are  some- 
times, though  less  frequently,  found  in  the 
first  intestine.  The  number  varies  consid- 
erably ;  sometimes  they  are  not  half  a  dozen, 
at  others  they  exceed  a  hundred.  They 
are  fixed  by  the  small  end  to  the  inner  coat 
of  the  stomach,  to  which  they  attach  them- 
selves by  means  of  two  hooks.  The  slow- 
ness of  their  growth,  and  the  purity  of  their 
food,  which  is  supposed  to  be  the  chyle, 
must  occasion  what  they  receive  in  a  given 
time  to  be  proportionably  small ;  from 
which,  perhaps,  arises  the  extreme  difficulty 
of  destroying  them  by  any  medicine  or  poi- 
son thrown  into  the  stomach."  A  large 
amount  of  opium,  tobacco,  and  corrosive 
sublimate,  sufficient  to  destroy  the  horse, 
have  from  time  to  time  been  given  ;  and,  on 
opening  the  stomach,  these  animals  have 
been  found  uninjured.  "  The  presence  of 
bots  in  the  horse's  stomach  is  not  easily 
ascertained,  as  it  is  certain  that  great  num- 
bers have  been  found  after  death  in  the 
stomach,  without  appearing  to  have  pro- 
duced any  kind  of  inconvenience  to  the  ani- 
mal while  alive.  It  does  not  appear  that 
any  effectual  remedy  has  yet  been  discov- 
ered for  bots."  Mr.  Blaine  says,  "  that  he 
has  kept  them  alive  for  some  days  in  olive 
oil,  and  in  oil  of  turpentine,  and  that  even 
the  nitrous  and  sulphuric  acids  do  not  im- 
mediately destroy  them.  At  a  certain  sea- 
son of  the  year,  they  detach  themselves  from 
the  stomach,  and  pass  off  with  the  excre- 
ment." A  run  at  grass  is  the  most  effec- 
tual remedy. 

Compound  for  Bots. — Persons  desirous 


of  treating  a  horse  for  bots,  can  use  the  fol- 
io win  sf  : 


Powdered 

poplar  bark, 

4  ounces. 

mandrake, 

.     2  ounces. 

balmony  (snaliehead),  . 

4  ounces. 

wormseed. 

.     2  ounces. 

goklen  vseal,  . 

1  ounce. 

slippery  elm,     . 

.     4  ounces. 

Mix.     Divide  into  sixteen  powders,  and  give  one,  night 
and  morning,  in  the  food. 

Regimen.  —  The  animal  should  be  kept 
on  a  generous  diet ;  green  food  or  succulent 
and  agreeable  vegetables  will  effect  a  change 
and  assist  to  detach  the  bots.  If,  however, 
such  articles  cannot  be  procured,  let  the 
horse  have  a  mess  of  scalded  shorts  every 
night. 

Bow-legged.  —  Defective  conformation 
of  the  legs. 

Box,  Loose. —  A  loose  box,  as  it  is  gen- 
erally called,  is  a  place  wherein  a  horse  is 
turned  without  being  fastened  to  the  man- 
ger or  rack  :  such  a  place  is  useful  to  turn  a 
horse  into  when  he  is  sick,  or  when  the  mare 
is  about  foaling. 

Brain.  —  The  connection  that  exists  be- 
tween the  brain  and  stomach,  by  means  of 
the  eighth  pair  of  nerves,  or  par  vagum,  is 
the  cause  of  this  important  organ  being 
often  disturbed  in  its  function.  Thus  it  is 
that,  when  the  stomach  is  loaded  with  food, 
its  function  becomes  deranged,  and  the  brain 
is  affected  sympathetically.  A  diseased 
action  is  then  set  up,  and  all  the  functions 
become  more  or  less  deranged.  A  horse  in 
this  case  will  become  dull  and  languid,  and 
sometimes  labor  under  symptoms  of  apo- 
plexy. In  consequence  of  this  nervous 
communication  between  the  stomach  and 
brain,  the  latter  organ  is  sometimes  affected 
by  the  irritation  of  bots  in  the  stomach. 
The  best  way  to  prevent  apoplexy,  staggers, 
etc.,  is,  by  attention  to  diet,  exercise,  etc. 

Dropsy  of  the  brain  does  not  often  occur 
to  horses  or  cows  ;  but  sheep  appear  to  be 
more  liable  to  the  disease  than  other  quad- 
rupeds. The  symptoms  of  the  disorder  in 
horses  are  variable.  "  In  one  case  there 
was  a  considerable  degree  of  dulness  and 
heaviness  about  the  head;  the  pulse  was 


228 


A    DICTIONARY. 


not  much  affected,  but  there  was  loss  of  ap- 
petite. The  animal  appeared  as  if  suffering 
much  pain  in  the  head,  generally  keeping  it 
lower  than  the  manger.  These  symptoms 
were  followed  by  delirium,  convulsions,  and 
death.  In  another  case,  when  probably  the 
water  had  accumulated  very  gi-adually  in 
the  ventricles  of  the  brain,  the  horse  ap- 
peared to  be  free  from  pain,  except  when 
the  circulation  was  hurried  by  brisk  motion, 
when  he  would  fall  down  in  violent  spasms, 
the  fit  seldom  lasting  but  a  few  minutes. 
This  horse,  being  of  scarcely  any  value,  was 
destroyed,  and,  upon  opening  the  brain, 
about  six  ounces  of  water  escaped."  Sir 
George  Mackenzie  has  described  two  kinds 
of  this  disease  which  sometimes  happen  to 
sheep :  "  The  first  consists  of  an  accumula- 
tion of  water  in  the  ventricles  of  the  brain ; 
the  other  —  which  is  most  common  —  arises 
from  animalculae,  called  hydatids.  In  this 
case,  the  water  is  contained  in  cysts,  or  bags, 
unconnected  with  the  substance  of  the  brain, 
on  which  it  acts  fatally  by  pressure.  Very 
soon  after  water  has  begun  to  collect,  either 
in  the  ventricles  or  cysts,  the  animal  shows 
evident  and  decisive  symptoms  of  the  dis- 
ease. He  starts,  looks  giddy  and  confused, 
as  if  at  a  loss  what  to  do  ;  retires  from  the 
flock,  and  sometimes  exhibits  a  very  affect- 
ing spectacle  of  misery." 

Breaking.  —  The  breaking  of  young 
horses  is  a  matter  of  great  importance,  and 
should  never  be  intrusted  to  any  one  of  a 
cruel  or  harsh  disposition,  as,  under  such  a 
master,  the  very  best-tempered  horse  may 
be  rendered  vicious.  They  are  often  broken 
when  much  too  young ;  they  are  often  found 
racing  at  tln-ee,  and  in  constant  work  before 
they  are  four  years  old.  This  is  one  of  the 
causes  of  contracted  feet  and  lameness,  that 
are  continually  presenting  themselves  to  our 
notice.  Farmers  in  general  put  their  colts 
to  work  too  young ;  and,  although  exercise 
may  improve  their  growth  and  constitution, 
yet  this  advantage  is  more  than  counter- 
balanced by  their  being  shod  at  a  period 
when  their  feet  are  tender. 

Bridle    Hand.  —  The  left  is  called  the 


bridle  hand,  in  contradistinction  to  the  right, 
which  is  termed  the  whip  hand. 

Broken  Wind.  —  The  origin  of  broken 
wind  is  supposed  to  be  a  morbid  secretion 
from  the  membrane  lining  the  windpipe, 
bronchial  tubes,  and  ramifications ;  the  air- 
cells  are  somewhat  ruptured,  and  the  air  is 
entangled  in  the  cellular  substance,  or  com- 
mon connecting  membrane.  The  bulk  of 
the  lungs  is  greatly  increased,  while  their 
capacity  for  containing  air  is  diminished. 
It  is  stated  in  Rees'  Cyclopcedia,  under  the 
head  of  broken  wind,  "  that,  after  opening 
more  than  ten  broken-winded  horses,  their 
lungs  were  uniformly  found  emphysemat- 
ous. (See  Emphysema.)  This  complaint 
is  generally  considered  incurable ;  but  it 
may  often  be  alleviated  by  constant  atten- 
tion to  diet."  The  animal  should  be  fed  on 
shorts,  and  green  food  if  it  can  be  procured, 
and  boiled  carrots.  When  used,  his  exer- 
cise should  at  first  be  moderate,  and  he 
should  never  be  exercised  immediately  after 
feeding.  If  the  horse  shows  any  disposition 
to  eat  the  litter,  a  muzzle  must  be  provided. 

According  to  Mr.  Richard  Lawi-ence, 
"  the  most  common  appearance  of  the  lungs 
in  broken-winded  horses  is  a  general  thick- 
ening of  their  substance,  by  which  their 
elasticity  is  in  a  great  measure  destroyed, 
and  their  weight  specifically  increased.  At 
the  same  time,  their  capacity  for  receiving 
air  is  diminished."  Dr.  White  writes,  "  that 
he  has  examined  the  lungs  of  broken-winded 
horses  without  observing  this  general  thick- 
ening of  their  substance ;  on  the  conti-ary, 
they  have  appeared  superficially  lighter  and 
larger  than  in  their  natural  state.  Two 
horses  were  purchased  for  the  purpose  of 
making  experiments,  and  so  badly  broken- 
winded  as  to  be  useless.  In  the  first,  the 
lungs  were  unusually  large,  and  there  was 
a  considerable  quantity  of  ah'  in  the  cellular 
membrane  ;  but  it  was  not  ascertained 
whether  the  air  had  escaped  from  the  air- 
cells,  or  had  been  generated  within  the 
common  cellular  membrane.  The  other 
horse  was  kept  about  a  month  in  a  field 
where  there  was  no  water  and  very  little 


A  DICTIONARY. 


229 


grass.  "When  taken  up,  he  appeared  per- 
fectly free  from  the  disorder.  He  was  shot ; 
and,  upon  examining  the  lungs,  they  had 
not  the  slightest  appearance  of  disease." 
This  proved  the  superiority  of  natui-e's 
i*emedies  over  those  of  man.  The  same 
author  relates  that  he  purchased  a  broken- 
winded  horse  that  was  incapable  of  work- 
ing. By  allowing  him  only  a  small  quan- 
tity of  hay,  sprinkled  with  water,  giving 
mashes,  mixed  with  a  small  quantity  of 
oats,  and  only  a  small  quantity  of  water, 
taking  care  at  the  same  time  that  he  had 
regular  and  moderate  exercise,  his  wind  be- 
came gradually  better,  and  he  afterwards 
was  perfectly  free  from  the  complaint. 

The  author  has  examined  the  lungs  of 
two  horses  which  were  said  to  be  afflicted, 
for  some  time  previous  to  death,  with  bro- 
ken wind,  without  detecting  a  loss  of  con- 
tinuity in  their  structure ;  neither  was  their 
specific  gravity  diminished. 

Bronchia. —  (See  Windpipe.) 

Bronchotomy. —  The  operation  of  open- 
ing the  windpipe  for  the  purpose  of  produc- 
ing artificial  respiration,  or  to  remove  any 
substances  that  may  have  lodged  in  the 
upper  part  of  the  larynx. 

Burns  are  best  treated  by  a  mixture  of 
equal  portions  of  lime-water  and  linseed 
oil,  the  parts  being  frequently  anointed  with 
the  mixture. 

BuRSiE  Mucosa.  Mucous  Bags,  or  Sacs. 
—  These  are  described  as  membranous  sacs, 
containing  a  fluid  similar  to  synovia,  or 
joint  oil,  and  interposed  between  tendons 
and  the  parts  on  which  they  move.  In 
violent  exertions  these  vascular  membranes, 
which  secrete  and  confine  the  synovia,  are 
injured  ;  hence  we  have  windgalls,  bog- 
spavin,  etc. 

BuTTERis.  —  An  instrument  used  by 
horse-shoers  for  paring  the  horse's  hoofs. 

Cjecvm. —  The  blind  gut.  So  named 
because  it  is  open  at  one  end  only.  In  the 
horse  this  part  of  the  intestines  is  remark- 
ably large. 

Calf,  Diseases  of. —  Many  of  the  dis- 
eases of  calves  originate  in  a  disordered 
state  of  the  stomach,  either  from  taking  too 


much  milk  at  a  time,  or  from  the  milk  not 
being  sufficiently  fresh,  or  being  taken  from 
a  cow  whose  health  is  impaired.  When- 
ever the  stomach  is  disordered,  either  by  the 
quantity  or  quality  of  the  milk,  it  causes  a 
variety  of  disorders,  such  as  scouring,  want 
of  appetite,  costiveness,  colic,  yellows,  con- 
vulsions, etc. 

Calkins. —  A  name  given  to  the  promi- 
nences on  horses'  shoes,  which  are  turned 
downward  for  the  purpose  of  preventing 
their  slipping. 

Calving. —  At  the  end  of  nine  lunar 
months  the  period  of  the  cow's  gestation  is 
complete ;  but  the  parturition  does  not  ex- 
actly take  place  at  that  time, —  it  is  some- 
times earlier,  at  others  later.  "  One  hun- 
dred and  sixteen  cows  had  their  time  of 
calving  registered :  fourteen  of  them  calved 
from  the  two  hundred  and  forty-first  day  to 
the-  two  hundred  and  sixty-sixth  day,  — 
that  is,  eight  months  and  one  day  to  eight 
months  and  twenty-six  days  ;  three  on  the 
two  hvmdi-ed  and  seventieth  day ;  fifty-six 
from  the  two  hundred  and  seventieth  to  the 
two  hundred  and  eightieth  day ;  eighteen 
from  the  two  hundred  and  eightieth  to  the 
two  hundred  and  ninetieth  day  ;  t\venty  on 
the  three  hundredth  day  ;  five  on  the  three 
hundred  and  eighth  day ;  consequently  there 
were  sixty-seven  days  between  the  two  ex- 
tremes. Immediately  before  calving,  the 
animal  appears  uneasy;  the  tail  is  elevated; 
she  shifts  about  from  place  to  place,  and  is 
frequently  lying  down  and  getting  up  again. 
The  labor  pains  then  come  on,  and,  by  the 
expulsive  power  of  the  womb,  the  foetus, 
with  the  membranes  enveloping  it,  is  pushed 
forward.  At  first  the  membranes  appear 
beyond  the  vagina  or  shape,  in  the  form  of 
a  bladder  of  water:  this  soon  bursts,  the 
water  is  discharged,  the  head  and  fore  feet 
of  the  calf  are  protruded  (in  natural  labor) 
beyond  the  shape.  The  body  next  appears, 
and  the  delivery  is  complete.  In  a  little 
time  afterwards,  some  triffing  pains  take 
place,  which  separate  the  afterbirth,  or 
cleansings ;  and,  these  being  expelled,  the 
process  is  finished. 

When  the   membrane   breaks,    and   the 


230 


A    DICTIONARY. 


fluid  escapes  early  in  calving,  and  before 
the  moutli  of  the  uterus  is  sulliciently  ex- 
panded, the  process  is  often  slow,  and  it  is 
a  considerable  time  before  any  part  of  the 
calf  makes  its   appearance.     The  practice 
of  hurrying  the  process  by  introducing  the 
hand,  or  driving  the  animal  about  when 
symptoms  of  calving  appear,  is  very  impro- 
per.    It  has  been  known  in  many  instances 
to  cause  the  animal's  death.     It  sometimes 
appears   that   a  wrong   presentation  takes 
place,  and  renders  the  calving  impracticable 
without   assistance.      In   such  cases   it   is 
necessary  to  introduce  the  hand  in  order  to 
ascertain  the  position  of  the  calf,  and  change 
it  when  it  is  found  unfavorable.     When, 
for  example,  the  head  presents  without  the 
fore  legs,  which  are  bent  under  the  breast, 
it  cannot,  in  this  position,  be  well  drawn 
away  without  danger.     In  this  case  the  calf 
should  be  gently  pushed  back  in  the  uterus, 
placing    the    cow   in   the    most    favorable 
position,  and  taking  the  opportunity  for  so 
doing  while  there  are  no  pains  nor  straining. 
When  the  calf  is  pushed  back,  the  fore  legs 
are  to  be  carefully  drawn  downward,  in  a 
line  with  the  head,  and  brought  out  into  the 
vagina.     The   author   has   known    several 
cases,  where  parturition  was  seemingly  dif- 
ficult, of  a  resort  to  force  in  extracting  the 
calf ;  but  it  should  be  recollected  that  nature 
is  never  to  be  interfered  with  in  the  process 
of  deKvery,  or  in  any  of  her  operations, 
unless  it  is  clearly  ascertained  that  assist- 
ance is  necessary.      When  much  force  is 
used  in  drawing  the  calf,  and  especially  if 
the   animal  be  rather  fat,  a  disease  of  the 
womb  is  apt  to  follow,  puerperal  fever  sets 
in,  which  often  proves  fatal.      Great  mis- 
chief is  also  done  by  endeavoring  to  extract 
the  calf  without  regard  to  its  position  in  the 
uterus :  it  is  sometimes  so  placed  that  de- 
livery is  not  practicable  until  the  position 
of  the  calf  is  shifted.     When  much  force 
is  used  in  drawing  the  calf,  it  sometimes 
happens  that  the  womb  falls  out  or  is  in- 
verted, and  great  care  is  required  in  putting 
it  back,  so  that  it  may  remain  in  its  situa- 
tion.    In  doing  so,  there  is    an  advantage 
derived   from  placing  the  cow  in   such  a 


position  that  the  hind  parts  may  be  higher 
than  the  fore.  If  any  dust  or  straw  remain 
about  the  womb,  they  should  be  carefully 
removed  before  the  womb  is  put  back.  A 
linen  cloth  is  then  to  be  put  under  the 
womb,  which  is  to  be  held  by  two  assistants. 
The  cdw  should  be  made  to  rise,  that  being 
the  most  favorable  position,  and  the  opera- 
tor is  then  to  grasp  the  mouth  of  the  womb 
with  both  hands,  and  gently  retm-n  it. 
When  so  returned,  one  hand  is  to  be  im- 
mediately withdrawn,  while  the  other  re- 
mains to  prevent  that  part  from  falling 
down  again.  The  hand  at  liberty  is  then 
to  grasp  another  portion  of  the  womb,  which 
is  to  be  pushed  into  the  body  lilie  the  former, 
and  retained  with  one  hand.  This  is  to  be 
repeated  until  the  whole  of  the  womb  is 
put  back  ;  if  the  womb  does  not  contract, 
friction  with  a  brush  around  the  belly  and 
back  may  excite  the  muscles  to  contraction: 
should  this  fail,  the  animal  may  have  an 
astringent  and  aromatic  drink,  made  by  in- 
fusing three  ounces  of  ground  poplar  bark 
in  about  three  pints  of  hot  water;  when 
cool,  administer  with  a  horn  or  bottle,  taking 
care,  while  pouring  down  the  oesophagus, 
to  let  it  fall  gently  and  gradually  ;  by  that 
means  it  will  pass  over  the  pillars  of  the 
OEsophagean  canal,  and  on  to  the  third 
stomach ;  otherwise  it  would  fall  into  the 
rumen,  and  defeat  the  object  in  view. 

Camphor.  —  A  narcotic  vegetable  concre- 
tion. This  medicine,  says  Dr.  White,  "  is 
employed  both  internally  and  externally.  It 
is  given  inwardly  as  an  anti-spasmodic,  as 
in  lockjaw,  when  it  is  commonly  joined  with 
opium  ;  and  as  a  febrifuge,  or  fever  medi- 
cine, joined  with  nitre  and  antimonial 
powder."  Mr.  Morton  writes :  Camphor 
has  been  occasionally  given  in  tympanitis, 
and  it  has  been  supposed  to  act  by  rousing 
the  vital  energies.  In  a  state  of  fine  powder 
it  is  sometimes  sprinkled  over  a  linseed- 
meal  poultice,  when  it  has  been  found  to 
allay  irritation  ;  although,  as  a  sedative,  thus 
applied,  it  is  not  equal  to  the  extract  of  the 
deadly  nightshade. 

On  account  of  its  sedative  influence,  it 
may   be    advantageously    combined   with 


A   DICTIONARY. 


231 


opium  or  digitalis  for  chronic  coughs. 
Given  for  any  length  of  time,  it  pervades 
the  system,  and  is  excreted  by  the  lungs  and 
kidneys. 

Cantharides.  —  Spanish  Fly*  —  Several 
preparations  of  cantharides  are  now  in  use 
for  example, 

Vinegar  of  Cantliarides. 
Talce  of  Catharides  in  powder,        .         1  part, 
"        Diluted  acetic  acid,      .        .     8  parts. 
Macerate  for  fom-teen  days,  and  filter. 

Oil  of  Cantharides. 
Cantharides  in  powder,      .         .  1  part. 

Olive  oil, 8  parts. 

Digest  in  a  water  bath  for  tsvo  hours,  and  filter  for  use. 

Ointment  of  Cantharides. 
Take  Cantharides  in  powder,     .  1  part. 

"         "         Hogs  lard,  .  .     6  parts. 

Digest  in  a  water  bath  and  filter  through  paper. 

Capped  Hock. —  A  swelling  on  the  point 
of  the  hock,  generally  occasioned  by  blows ; 
they  seldom  cause  lameness ;  but,  as  they 
are  a  considerable  blemish,  an  attempt 
should  be  made  to  reduce  them  by  counter- 
irritants  ;  friction  is  also  useful. 

Capsicum.  —  In  its  pure  state  it  contains 
tonic  and  stimulant  properties.  It  increases 
the  physiological  or  healthy  action  of  the 
system. 

Capsular  Ligament. —  The  ligament  by 
which  two  bones  are  joined  together.  It 
forms  a  complete  sac  round  them,  and  serves 
to  confine  the  synovia,  or  joint  oil. 

Caraway  Seeds.  —  These  are  cordial 
and  carminative.  The  dose  is  from  one  to 
two  ounces. 

Carbon. —  Pure  charcoal,  unmixed  with 
any  foreign  body.  It  is  ■  antiseptic  and 
absorbent ;  useful  as  a  poultice  for  putrid 
sores. 

Carditis.  —  Inflammation    of  the  heart. 

Caries.  —  Ulceration  or  rottenness  of  a 
bone. 

Carminatives. —  Medicines  that  correct 
flatulency,  or  expel  wind  ;  the  principal  of 
these  are  the  caraway  and  fennel  seeds. 

Carotid  Artery.  —  A  large  artery,  that 
runs  on  each-  side  of  the  neck,  near  the 
windpipe.     The  jugular  vein  runs  immedi- 

*  Morton's  Jlanual. 


ately  over  the  artery.  Yet  at  the  upper  part 
of  the  neck  they  are  at  such  a  distance  that 
there  is  no  danger  of  wounding  the  latter  in 
bleeding. 

Cartilage.  —  Gristle.  A  smooth,  elastic 
substance  attached  to  bones.  Cartilages 
are  situated  in  parts  where  elasticity  is 
required  ;  they  render  the  parts  connected 
with  them  capable  of  slight  changes  of  form, 
and  instant  recovery,  to  accommodate  them- 
selves to  accidents  and  circumstances,  with- 
out serious  injury  to  themselves.  There  are 
also  inter-articular  cartilages ;  that  is,  flat, 
smooth  cartilages,  between  the  ends  of  two 
bones.  These,  being  covered  with  synovia, 
or  joint  oil,  serve  to  facilitate  the  motion  of 
the  joint. 

Castor. —  A  peculiar  matter  found  in 
sacs,  near  the  rectum  of  the  beaver.  It  is 
used  as  an  anti-spasmodic,  in  doses  of  two 
drachms  (for  a  horse),  mixed  in  thin  gruel. 

Castration. —  An  operation  often  per- 
formed on  horses,  and  other  domestic  ani- 
mals. The  best  method  of  performing  it  is 
by  means  of  the  clams,  and  ligature. 

Cataplasm,  or  Poultice.  —  This  appli- 
cation, when  designed  to  promote  suppura- 
tion, or  formation  of  matter,  is  best  made 
by  mixing  together  equal  parts  of  slippery 
elm  and  flax-seed,  pouring  a  sufficient 
quantity  of  boiling  water  on  the  mixture,  to 
make  it  of  the  consistence  of  mush,  and 
binding  it  on  the  part ;  the  bandage  should 
not  be  so  tight  as  to  interfere  with  the 
return  of  blood  by  the  veins.  A  poultice 
should  always  be  renewed  every  twelve 
hours. 

Cataract.  —  A  disease  of  the  horse's 
eye.  A  cataract  may  be  partial  or  total. 
The  partial  cataract  is  known  by  specks  in 
the  pupil,  which  interrupt  vision  in  propor- 
tion to  their  size,  and  according  to  their 
situation.  In  the  total  or  complete  cata- 
ract, the  whole  of  the  pupil  becomes  of  a 
white  or  pearl  color.  A  horse's  sight  is  least 
injured  by  partial  cataract,  when  the  speck 
is  most  remote  from  the  centre  of  the  pupil, 
and  near  to  the  upper  margin.  When  a 
complete  cataract  takes  place  in  one  eye, 
the    strength  of   the  other  becomes  estab- 


232 


A    DICTIONARY. 


lished,   so   that   the  horse  soon  accommo- 
dates himself  to  the  loss. 

Catarrh,  or  Cold.  —  This  is,  perhaps,  a 
disorder  more  common  in  horses  than  any 
other.  The  author  attributes  some  colds  (in 
this  city)  to  the  bountiful  use  of  Cochituate 
water.  When  the  horse  has  just  arrived 
from  a  journey,  or  is  in  a  state  of  perspira- 
tion, the  showering  process,  so  much  in 
fashion  just  now,  is  decidedly  injmious.  If 
the  legs  of  the  animal  are  sluiced  with  water, 
and  he  is  afterwards  suffered  to  stand  where 
a  current  of  air  blows  on  him,  he  is  likely  to 
take  cold.  Horses  accustomed  to  warm 
clothing  and  warm  stables  are,  of  course, 
most  liable  to  cold.  The  symptoms  are 
cough,  dulness,  want  of  appetite,  discharge 
from  the  nostrils,  frequently  accompanied 
by  sore  throat  and  difficvilty  of  swallowing. 

Catarrh,  Epidemic. —  The  epidemic  ca- 
tarrh is  so  named  from  its  spreading  over  a 
country  as  a  general  disorder,  often  for  a 
considerable  time.  When  the  disease  is  so 
prevalent,  it  is  supposed  to  depend  on  a  cer- 
tain state  of  the  atmosphere. 

Catheter. —  A  gum  elastic  tube,  for  the 
purpose  of  di-awing  off  the  urine.  The  one 
used  for  the  horse  is  about  four  feet  in 
length. 

Caustics. —  Preparations  that  destroy 
the  part  to  which  they  are  applied. 

Cellular  Membrane. —  The  substance 
by  which  various  parts  of  the  body  are 
united  to  each  other.  The  cells  of  which 
this  structure  is  composed  communicate 
with  each  other;  which  is  proved  by  mak- 
ing a  small  opening  in  Ihe  skin  of  an  ani- 
mal, introdvicing  a  blow-pipe,  and  blowing 
through  it,  by  which  the  adjacent  skin  will 
puff  up ;  if  sufficient  power  were  employed, 
the  air  may  be  thus  forced  all  over  the  body. 

Cerebellum. —  The  small  brain.  It  is 
situated  immediately  behind  the  cerebrum, 
or  large  brain,  and  upon  the  origin  of  the 
spinal  marrow. 

Chest  Founder. —  (See  Founder.) 

Chronic. —  A  term  used  to  denote  a  dis- 
ease of  long  standing,  unaccompanied  by 
fever  or  inflammation. 

Chyle.  —  A  milky  fluid,  formed  by  the 


action  of  the  gastric,  pancreatic,  and  bilious 
fluids.  Chyle  is  absorbed  and  carried  by 
the  lacteals  to  the  thoracic  duct;  but,  pre- 
vious to  its  arrival  there,  it  passes  through 
the  mesenteric  glands,  where,  probably,  it 
undergoes  some  change. 

Cicatrix.  —  The  mark  that  remains  after 
a  sore,  wound,  or  ulcer  has  been  healed. 

Circulation  of  the  Blood.  —  (See 
Heart.) 

Clipping.  —  Cutting  the  long,  rough  hair 
of  a  horse.  It  is  chiefly  done  to  improve 
the  appearance  of  the  horse.  The  author 
doubts  its  utility.  (See  article  Hair,  part 
first.) 

Clothing.  —  A  pernicious  custom  is 
often  adopted  of  keeping  horses  clothed  in 
the  stable ;  making  no  difference  in  the 
warmth  of  the  clothes,  whatever  the  season 
of  the  year  or  the  state  of  the  weather  may 
be.  (This  custom  is  not  so  prevalent  here 
as  in  England.)  In  a  good  stable,  it  is 
probable  that  even  in  winter  it  might  be  dis- 
pensed with ;  and  a  horse  will  then  be  much 
less  liable  to  take  cold,  when  he  happens  to 
stand  in  a  cold  wind  or  rain.  When  a  horse 
is  moulting,  or  shedding  his  coat,  light  cloth- 
ing might  be  useful ;  and,  at  such  periods, 
showering,  or  standing  out  in  the  rain, 
would  be  very  injurious.  In  summer,  the 
horse  should  have  a  net  throAvn  over  him  to 
protect  him  from  the  flies. 

Clysters,  or  Glysters. —  A  liquid 
preparation,  forced  into  the  rectum  by  means 
of  a  syringe. 

Coffin  Bone,  or  Os  Pedis. —  The  bone 
which  is  inclosed  by  the  hoof. 

Coffin  Joint.  —  (See  Hoof.) 

Colic. —  A  very  common  disease  in 
horses.  It  begins  with  an  appearance  of 
uneasiness ;  he  paws  his  litter ;  sometimes 
makes  ineffectual  attempts  to  stale ;  stamps 
with  his  feet ;  gathers  up  his  legs,  and  lies 
down  heavily ;  groans,  and  looks  round  to 
his  flank ;  lies  down  heavily  again,  as  before, 
and  rolls  on  his  back.  The  body  sometimes 
swells.  If  relief  is  not  promptly  afforded, 
all  the  above  symptoms  gradually  increase ; 
the  pulse  becomes  quick,  the  breathing  dis- 
turbed, and  the  pain  is  so  great  that  a  vio- 


A   DICTIONARY. 


233 


lent  perspiration  breaks  out,  and  the  hojse 
becomes  almost  delirious,  throwing  himself 
about  the  stall,  so  that  it  is  dangerous  to 
come  near  him. 

Condition. —  This  term  is  used  to  imply 
a  horse  being  in  perfect  health. 

Conjunctiva.  —  The  external  coat  or 
membrane  of  the  eye.    (See  Eye,  part  first.) 

Consumption.  —  In  consumption  there  is 
a  gradual  loss  of  flesh  and  strength,  while 
the  appetite  is  seldom  impaired  in  the  early 
stages.  It  is  sometimes  accompanied  by  a 
discharge  from  one  or  both  nostrils,  and  a 
swelling  of  the  glands  under  the  jaw ;  such 
cases  are  often  mistaken  for  glanders.  Con- 
sumption does  not  often  take  place  sud- 
denly, but  is  very  insidious  in  its  attack ; 
and  it  often  happens,  that  the  complaint  is 
not  much  noticed  till  tubercles  are  formed 
in  the  lungs,  and  the  mesenteric  glands  are 
diseased.  When  a  horse  is  observed  to  lose 
flesh,  his  coat  staring,  his  skin  feeling  as  if 
fast  to  the  ribs,  he  should  be  warmly 
clothed,  and  fed  on  scalded  shorts,  oats,  and 
boiled  carrots ;  by  proper  attention  to  stable 
management,  he  may  gain  flesh  and  strength, 
his  coat  will  become  smoother,  and  his  skin 
looser.  Should  it  now  be  the  season  of  the 
year  when  good  grass  can  be  procured,  this 
will  perfect  the  recovery.  The  best  medi- 
cines are  cod  liver  oil  and  phosphate  of  lime. 

Contagion. —  The  mode  in  which  a  dis- 
ease is  communicated  from  one  animal  to 
another.  It  is  derived  from  the  word  contact, 
or  touch,  and  is  used  in  contradistinction 
to  infection,  which  implies  the  commu- 
nication of  disease  by  unwholesome  mias- 
mata, sometimes  spreading  to  a  very  con- 
siderable distance. 

Convalescence.  —  A  state  of  recovery 
from  illness,  or  an  approach  to  a  state  of 
health. 

Convulsions.  —  Under  this  name,  Gib- 
son has  classed  lockjaw  and  staggers. 
Modern  ^vriters  treat  of  these  diseases  under 
their  respective  heads.  Calves  are  subject 
to  convulsive  diseases,  from  indigestion,  and 
the   consequent   formation  of  acid   in   the 

stomach.     It  is  often  occasioned  by  some 
so 


bad  quality  in  the  millc  they  drink,  when 
fed  by  hand.  Taking  too  much  milk  will 
often  brino^  on  the  disorder.  Carminatives 
and  tonics  generally  afford  relief;  after 
which,  it  is  necessary  to  be  more  attentive 
to  the  future  mode  of  feeding,  giving  a  little 
gruel  occasionally. 

Cordials.  —  Medicines  are  thus  termed 
that  possess  warm  and  stimulating  proper- 
ties, such  as  ginger,  caraway  seeds,  anise 
seeds,  etc. 

Cornea.  —  The  outer  transparent  part  of 
the  eye. 

Corner  Teeth.  —  The  outermost  of  the 
front  teeth  are  thus  named. 

Corns. — Corns  generally  appear  at  the  in- 
ner angles  of  the  fore  feet,  from  injuries,  etc. 

Coronet  Bone. —  Os  corona.  The  sec- 
ond of  the  consolidated  phalanges  of  the 
horse's  foot. 

Coronet.  —  The  upper  part  of  the  hoof, 
where  the  horn  terminates. 

Corrosive  Sublimate.  —  Among  the 
poisons  that  are  given,  with  a  view  of 
curing  disease,  corrosive  sublimate  seems  to 
stand  foremost  in  the  destruction  of  vitality, 
and  the  production  of  incurable  diseases. 
Dr.  White  remarks :  "  It  is  necessary  to 
observe  carefully  its  effects ;  for,  whenever 
it  takes  off  the  appetite,  or  causes  uneasi- 
ness of  the  stomach  or  bowels,  it  should  be 
immediately  discontinued.  A  solution  of 
corrosive  sublimate  in  water  has  been  em- 
ployed as  a  lotion  in  mange,  but  is  gener- 
ally considered  dangerous  ;  a  fatal  disorder 
of  the  bowels  having  in  several  instances 
followed  its  use.  Five  cows,  that  were 
bathed  with  a  solution  of  corrosive  subli- 
mate in  tobacco  water,  died  soon  after. 

Cough.  —  A  cough  is  sometimes  the  first 
symptom  of  a  cold,  or  catarrh ;  but  there 
is  another  kind  of  cough,  which  accompa- 
nies indigestion.  Horses  that  eat  too  much 
hay,  and  drink  a  large  quantity  of  water, 
often  have  chronic  cough.  This  can  be 
removed  by  proper  attention  to  feeding. 

Cows,  Disease  of. —  The  disorders  of 
cows  are  not  so  numerous  as  those  of  the 
horse  ;  they  are  often  brought  on  by  feeding 


234 


A    DICTIONARY. 


A  disagreeable  and  in- 


on  improper  food,  or  by  being  kept  on  low, 
marshy  grounds.  Cattle  that  arc  brought 
from  a  warm  to  a  colder  climate,  and  such 
as  are  naturally  of  weak  constitution,  are 
most  liable  to  disease. 

Cramp. —  A  spasmodic  affection  of  the 
muscles,  either  of  a  particular  part,  or  of  the 
whole  body.  In  lockjaw,  for  example,  the 
muscles  of  the  jaw  are  at  first  chiefly  affect- 
ed ;  but,  gradually,  unless  relief  is  afforded, 
the  spasm,  or  cramp,  generally  extends  to 
the  neck,  limbs,  and  at  length  to  all  parts 
of  the  body. 

Crassamentum.  —  Red  globules,  or  color- 
ing matter,  of  the  blood,  mixed  with  coagu- 
lable  lymph. 

Cremaster.  —  A  muscle  which  surrounds 
the  spermatic  cord,  as  it  passes  out  of  the 
belly  into  the  scrotum.  Its  use  is  io  sus- 
pend and  draw  up  the  testicle. 

Crib  Biting 
jurious  habit,  which  some  horses  acquire ; 
it  consists  of  laying  hold  of  'the  manger 
with  their  teeth.  It  generally  proceeds  from 
indigestion. 

Cropping  the  Ears.  —  The  ear  may  be 
inclosed  between  the  two  parts  of  a  car- 
penter's rule,  which  can  be  adjusted  and 
held  so  as  to  give  the  ear  any  shape  that 
may  be  required.  All  that  part  outside  the 
rule  is  then  cut  off  with  one  stroke  of  a 
sharp  knife,  and  then  bathed  with  tincture 
of  myrrh. 

Crupper. —  A  strap  affixed  to  the  saddle, 
with  a  loop  at  the  end,  for  the  purpose  of 
admitting  the  horse's  tail. 

Cud.  —  The  food  contained  in  the  first 
stomach,  or  rumen,  of  a  ruminating  animal, 
which  is  returned  to  the  mouth  to  be  chewed 
at  the  animal's  leisure. 

Cumin  Seeds. — A  carminative,  or  cordial. 

Curb. —  A  swelling  of  the  horse's  hock, 
generally  causc-d  by  blows  or  strain. 

Cutaneous  Diseases.  —  Diseases  whose 
seat  is  in  the  skin,  as  the  mange,  for  ex- 
ample. They  are  generally  dependent  on 
a  vitiated  state  of  the  secretions,  and  a  dis- 
ordered state  of  the  bowels. 

Cuticle,  or  Scarf  Skin.  —  A  thin,  in- 
sensible membrane,  which   covers   and  de- 


fends the  true  skin.  It  is  this  which  forms 
the  bladder  raised  by  blistering. 

Cutis.  —  The  skin,  or  hide,  which  lies 
under  the  cuticle.  Besides  the  cuticle  and 
skin,  horses  and  other  large  animals  have  a 
muscular  expansion,  which  lies  immediately 
under  the  latter,  called  the  fleshy  pannicle, 
by  which  the  skin  is  moved,  so  as  to  shake 
off  dust  or  flies,  or  anything  that  hangs 
loose  upon  the  hair. 

Cutting.  —  A  horse  is  said  to  cut,  when 
he  strikes  the  inner  and  lower  part  of  the 
fetlock  joint,  in  travelling.  The  usual  mode 
of  correcting  this,  is  to  make  the  outer  side 
of  the  shoe  higher  than  the  inside. 

Debility.  —  Debility  may  be  permanent 
or  temporary.  In  the  first,  the  constitution 
is  naturaUy  weak,  or  has  been  rendered  so 
by  improper  treatment,  or  sickness ;  the 
second  generally  arises  from  over-exertion, 
and,  if  the  exciting  cause  be  frequently  re- 
peated, terminates  very  commonly  in  a  total 
decay  of  the  constitution.  Rest  and  kind 
treatment  are  the  best  cure  for  weakness  in- 
duced by  fatigue.  The  greatest  attention 
should  be  paid  to  the  degree  of  work  that 
a  horse  is  capable  of  enduring,  as  what 
may  be  salutary  for  him  at  one  period  may 
greatly  exceed  his  strength  at  another;  and 
this  generally  depends  on  the  mode  of  sta- 
ble management.  The  common  practice 
of  working  horses  too  early  frequently 
results  in  debility. 

Decoction.  —  The  process  of  extracting 
the  virtues  of  a  substance  by  boiling  it  in 
water.  The  liquid  so  prepared  is  termed 
decoction.  Almost  all  the  medicinal  prop- 
erties of  plants  may  be  extracted  by  pour- 
ing boiling  water  over  them.  In  boiling 
they  lose  their  volatile  properties. 

Deglutition. —  The  act  of  swallowing. 
The  power  of  swallowing  is  often  impeded 
in  the  horse  by  sore  throat,  distemper,  etc. 
This  impediment  is  only  of  a  temporary 
nature ;  but  there  is  another,  which  is  of  a 
more  serious  kind,  and  interferes  with  mas- 
tication as  well  as  with  swallowing.  The 
grinding  teeth  of  horses  often  wear  down 
in  such  a  manner,  that  the  outside  edge  of 
the  upper  grinders  irritates  or  wounds  the 


A   DICTIONARY. 


235 


cheek,  and  the  inside  of  the  lower  gi-inders 
acts  similarly  upon  the  tongue,  or  the  skin 
connected  with  it.  Whenever  a  horse  is 
observed  to  void  unbroken  oats  with  his 
dung,  the  teeth  and  cheeks  should  be  ex- 
amined. It  will  often  be  found  necessary 
to  rasp  the  outside  edges  of  the  upper 
grinders,  and  sometimes  the  inner  edges  of 
the  lower  ones. 

Demulcents.  —  Medicines  of  a  mucila- 
ginous kind,  which  sheath  the  mucous 
membranes  when  they  are  tender  and  irri- 
table, and  defend  them  from  the  action  of 
what  would  otherwise  injure  them.  Of 
this  kind  are  marsh  mallows,  linseed  tea, 
solution  of  gum  arable. 

Dentition. —  The  act  of  changing  the 
teeth,  which  is  going  on  from  the  second  to 
the  fifth  year.  During  this  period,  the  horse's 
mouth  is  apt  to  become  tender,  which  ren- 
ders it  necessary  to  keep  him  for  a  short 
time  on  scalded  shorts,  or  boiled  carrots. 

Diabetes.  —  An  excessive  discharge  of 
urine,  accompanied  by  thirst  and  debility. 
There  are  three  outlets  for  the  fluids  of  the 
body, —  the  surface,  the  lungs,  and  the 
urinary  passage.  When  either  is  deficient 
in  action,  one  or  both  of  the  others  must 
make  up  that  deficiency ;  so,  excess  in  one 
produces  deficiency  in  the  others  ;  hence,  in 
diabetes  we  often  find  a  dry  skin  and  stare- 
ing  coat ;  and  in  excessive  perspiration,  the 
urine  is  scanty,  whatever  be  the  organs 
affected  or  whether  the  one  or  the  other  be 
excessive  or  diminished.  The  indications 
are,  to  equalize  the  action  of  these  opposing 
or  sympathizing  surfaces,  by  restoring  the 
diminished  secretions,  and  cleansing  and 
toning  the  organ  whose  action  is  excessive. 
All  direct  efforts  to  produce  specific  effects, 
without  regard  to  a  balance  of  action 
through  the  whole  animal,  do  more  harm 
than  good. 

Diaphoretics.  —  Medicines  that  promote 
insensible  perspiration,  or  excite  moderate 
sweating.  Of  this  class  are  lobelia  and 
emetics,  given  in  infusion. 

Diaphragm,  Midriff,  or  Skirt. —  A  mus- 
cular and  tendinous  expansion,  which  divides 


the  cavity  of  the  chest  from  the  abdomen, 
or  belly. 

DiARRHCEA,  or  PuRGiNG.  —  111  Professor 
Percivall's  lectures  on  diarrhoea,  he  states 
that,  "  for  the  majority  of  cases  brought  to 
us,  we  are  indebted  to  the  groom,  the  far- 
rier, and  stable-keeper,  who  used  to  kill 
many  horses  by  literally  purging  them  to 
death.  Thirty  years  ago,  an  ounce  and  a 
half  or  two  ounces  of  aloes,  occasionally 
combined  with  one  or  two  drachms  of 
calomel,  composed  the  common  purge  ;  and 
even  now,  among  these  people,  nine,  ten, 
and  eleven  drachms  are  by  no  means  un- 
usual doses.  Young  horses,  on  their  first 
arrival  in  the  metropolis,  are  all  physicked ; 
they  have  given  to  them,  indiscriminately, 
doses  of  aloes,  every  one  of  which  would 
be  sufficient  to  purge  two  of  them ;  the  re- 
sult is,  that  the  light-carcassed,  irritable 
subject  is  carried  off"  at  once  by  superpurga- 
tion,  while  another,  or  two,  may  linger  in 
misery  and  pain  from  a  dysentery  that  will 
end  in  gangrene  and  death,  or  be  rendered 
more  speedily  fatal  by  the  doses  of  opium, 
or  some  other  powerful  astringent,  which 
are  so  perniciously  resorted  to  on  these 
occasions.  There  is  another  not  uncommon 
cause  of  this  disease,  and  that  is,  continuous 
and  excessive  exertion.  After  having  been 
ridden  for  many  hours,  a  horse  will  often 
express  irritation  in  the  bowels,  by  fre- 
quently voiding  his  excrement,  which  will 
be  found  to  be  enveloped  in  a  slimy  or 
mucous  matter,  that  is  called  by  some 
molten  grease." 

DiLUTENTS.  —  Those  substances  that  in- 
crease the  fluidity  of  the  animal  economy. 
Water  may  be  justly  considered  as  the  only 
dilutent. 

Director. —  A  grooved  instrument,  made 
for  the  purpose  of  conducting  the  knife  in 
open  sinuses,  and  in  several  other  opera- 
tions of  surgery. 

Dislocation.  —  A  displacement  of  a 
bone  from  its  socket.  A  dislocation  of  the 
fetlock  joint  may  be  replaced,  and  kept  in 
its  position  by  bandages ;  the  horse  should 
not  take  any  exercise  until  it  is  completely 


236 


A   DICTIONARY. 


healed.  A  dislocation  of  the  stifle,  or 
patella,  must  be  reduced  by  brini^ing  the 
horse's  leg  under  the  belly,  and  then  depress- 
ing the  outer  angle  of  the  patella,  or  stifle 
bone,  with  the  hand,  which  gives  the 
muscles  the  power  to  draw  the  bone  into  its 
place.  Generally  speaking,  dislocations  are 
rare. 

Distemper.  —  This  name  is  applied  to 
diseases  that  prevail  at  particular  periods, 
and  spread  to  a  considerable  distance. 
(See  Epidemic.) 

Docking. —  Cutting  off  part  of  the  tail. 
If  this  is  ever  necessary  (and  the  author 
doubts  it),  then  the  operation  should  be 
performed  before  the  animal  is  two  years 
old. 

Drastic. —  A  term  applied  to  purgatives 
that  operate  powerfully. 

Drenches,  or  Drinks.  —  When  it  is 
necessary  that  any  medicine  should  operate 
speedily,  this  is  the  best  form  in  which  it 
can  be  given.  A  bottle  with  a  short  neck  is 
the  best  drenching  instrument.  In  giving  a 
drench,  the  tongue  should  be  at  liberty,  the 
head  moderately  elevated ;  the  drench  is 
then  poured  down  moderately.  The  head 
is  to  be  kept  in  an  elevated  position  until 
the  drench  is  swallowed.  If  the  animal 
happens  to  cough  while  the  drench  is  in  his 
throat,  the  head  should  be  immediately  let 
down. 

Dressing.  —  A  term  employed  to  desig- 
nate medical  applications  to  a  wound,  or 
ulcer,  and  the  operation  of  cleaning  a  horse. 

Dropsy.  —  This  disease  consists  in  a  col- 
lection of  serous  or  watery  fluid,  either  in 
cavities,  as  the  chest,  belly,  or  ventricles  of 
the  brain,  or  in  the  cellular  membrane  under 
the  skin.  Dropsy  is  more  a  symptom  of 
disease  than  a  disease  itself;  but  some- 
times, on  account  of  the  violence  and  danger 
of  the  symptom,  it  is  often  treated  as  a 
disease.  The  proximate  cause  is  a  check  to 
perspiration ;  the  remote  cause  is  bleeding, 
or  any  thing  that  can  debilitate  the  general 
system. 

Dropsy  of  the  Chest.  —  This  is  some- 
times a  consequence  of  disease  of  the  lungs  ; 
and,  when    it    happens,   those   important 


organs  generally  are  so  far  disorganized,  or 
injured,  that  there  is  very  little  chance  of  the 
animal's  recovery. 

Dropsy  of  the  Belly,  or  Ascites.  — 
The  causes  are  the  same  as  above  ;  the  only 
difference  is,  that,  from  circumstances  pre- 
disposing, the  fluid  is  determined  on  the 
peritoneum  (see  Peritoneum)  instead  of 
the  pleura. 

Duct. —  A  membranous  tube,  or  canal, 
through  which  certain  fluids  are  conveyed. 
Thus  the  lachrymal  duct  conveys  tears  from 
the  eyes  to  the  nose. 

Dung. —  By  examining  a  horse's  dung, 
we  are  enabled  to  judge  of  the  state  of  his 
health.  When  the  dung  is  hard,  and  in 
small  knobs,  and  covered  with  slime,  laxa- 
tive medicines  are  beneficial ;  and  when  it 
is  passed  in  too  great  quantities,  it  com- 
monly arises  from  too  liberal  allowance  of 
food.  If  oats  are  voided  whole,  it  will 
generally  be  found  to  be  caused  either 
by  a  defect  of  the  teeth,  or  by  a  too 
voracious  appetite,  occasioning  the  food 
to  be  swallowed  without  mastication ;  in 
which  case  the  animal  should  be  fed  on 
shorts,  or  scalded  food. 

Duodenum.  —  The  first  intestine  that 
comes  from  the  stomach.  (See  Intes- 
tines.) 

Dura  Mater.  —  A  strong  membrane  that 
invests  the  brain  and  divides  it  into  two 
lobes.  It  likewise  separates  the  large  brain 
(cerebrum)  from  the  small,  or  cerebellum. 

Ear.  —  The  horse's  ear  is  merely  an  organ 
for  collecting  sound ;  consequently  he  has 
complete  power  over  the  muscles  attached 
to  them,  and  can  turn  them  in  different 
directions. 

Effluvia.  —  Invisible  vapors  that  arise 
from  bodies. 

Effusion.  —  The  oozing  out  of  serum,  or 
coagulable  lymph,  from  the  blood-vessels. 

Embrocation.  —  A  liquid  preparation  for 
rubbing  upon  the  skin,  and  generally  used 
for  strains,  bruises,  and  enlarged  glands. 

Embryotomy,*  —  When,  from  weakness, 
a  very  narrow  pelvic  opening  on  the  fore  part 
of  the  mother,  or  monstrosity  on  the  part  of 
*  Blaine. 


A   DICTIONARY. 


237 


the  foal,  no  efforts  can  bring  the  foetal  mass 
away  entire,  it  must  be  dismembered.  A 
knife  made  for  the  purpose,  having  the  blade 
concealed,  with  the  haft  lying  within  the 
hollow  of  the  hand,  is  to  be  taken  up  into 
the  vagina.  We  are  told  that,  occasion- 
ally, hydrocephalus  in  the  colt  prevents 
the  head  from  passing.  Such  a  case 
wiU  detect  itself  by  the  volume  that  will 
be  felt  on  examination,  and  which  will 
be  easily  lessened  by  plunging  the  point  of 
the  knife  in  the  forehead,  and  evacuating  the 
contents  by  pressing  the  skull  in ;  when, 
laying  hold  of  the  muzzle,  the  head  may  be 
brought  through  the  pelvic  opening.  But  it 
is  usually  the  natural  size  of  the  head  which 
forms  the  obstruction ;  in  which  case  the 
head  itself  must  be  removed.  When  the 
head  has  been  dissected  off  and  brought 
away,  it  wiU  be  necessary  probably  to  con- 
tract the  volume  of  the  chest;  which  will 
not  be  difficult,  by  cutting  the  cartilaginous 
portions  of  the  ribs,  detaching  the  thoracic 
viscera,  and  then  crushing,  or  rather  mould- 
ing, the  empty  thorax  together  ;  after  which 
the  rest  of  tlie  body  will  offer  little  obstruc- 
tion. When  the  head  cannot  be  got  at,  the 
limbs  must,  one  by  one,  be  detached :  after 
which  the  body,  and  at  last  the  head,  may 
be  drawn  out  either  entire,  or  lessened  con- 
siderably. 

Emetic,  Tartar.  —  Tartarized  antimony. 
A  coiTosive  metallic  poison.  Dr.  White 
relates  :  "  From  examining  the  stomachs  of 
horses  that  have  taken  this  mineral,  I  am 
satisfied  that  irreparable  mischief  may  be 
done  with  it,  and  certain  it  is  that  a  vast 
deal  of  unnecessary  pain  'has  been  thus 
inflicted." 

Emphysema. —  Swellings  which  contain 
air.  Such  swellings  are  known  by  a  kind  of 
crackling  noise,  or  sensation,  when  they  are 
pressed  with  the  finger. 

Emulgent  Arteries. —  The  arteries 
which  convey  blood  to  the  kidneys. 

Encanthis. —  A  disease  of  the  inner 
corner  of  the  eye. 

Encysted.  ^ — A  term  applied  to  tumors 
which  consist  of  a  solid  or  liquid  substance, 
contained  in  a  sac,  or  cyst. 


Enteritis. — Inflammation  of  the  bowels. 
This  is  a  very  serious  form  of  disease,  and  is 
the  result  of  plethora,  or  the  sudden  applica- 
tion of  cold  to  the  surface.  It  is  sometimes 
owing  to  an  overloaded  state  of  the  stom- 
ach and  bowels.  Obstinate  spasm  will  also 
produce  it. 

Epidemic.  —  Diseases  which  spread  over  a 
whole  country,  at  certain  seasons,  are  thus 
named.  If  many  suffer  in  the  same  manner, 
it  is  called  epizootic.  There  are  very  few 
diseases  which  assume,  in  its  latter  or  earlier 
stages,  such  a  variety  of  forms ;  perhaps 
depending  on  the  location,  and  the  peculiar 
state  of  the  constitution.  Youatt  writes : 
"  In  1711,  an  epidemic  commenced,  which, 
although  it  sometimes  suspended  its  ravages, 
would  visit  new  districts  ;  it  also  appeared 
in  a  certain  district,  and  confined  itself  to 
that  location.  In  1747,  it  appeared,  and 
would  seem  as  if  there  was  a  strange  caprice 
about  it.  It  would  select  its  victims,  the 
best  of  the  herd,  around  a  certain  district, 
and  confine  itself  to  that  location  for  a  short 
time ;  then  disappear  for  several  months, 
return,  and  pounce  upon  this  privileged  spot. 
In  some  districts,  it  would  attack  the  mouth 
and  throat;  commencing  with  a  loss  of 
appetite  and  difficult  respiration,  terminat- 
ing with  a  discharge  of  blood  from  the 
anus.  Sometimes  the  animals  will  eat  and 
work  until  they  suddenly  expire ;  others  will 
linger  in  dreadful  agony."  It  appears  that 
this  malady  is  not  infectious ;  for  the  same 
author  writes:  "  Cattle  were  in  the  same 
barn  as  those  infected  ;  they  ate  of  the  same 
fodder  that  the  distempered  beasts  had 
slavered  upon,  drank  after  them,  and  con- 
stantly received  their  breath  and  odor, 
without  being  the  least  affected.  In  1756, 
it  assumed  a  different  form ;  some  cattle 
were  taken  all  at  once  with  violent  trem- 
bling of  every  limb,  and  blood  ran  from  the 
nose,  and  bloody  slime  from  the  mouth,  and 
the  animals  died  in  a  few  hours." 

Epiglottis. — The  cartilage  which  covers 
the  larynx,  or  top  of  the  windpipe,  at  the 
time  food  or  water  is  passing  into  the  gullet. 

Epilepsy.  —  The  faffing  sickness  ;  fits. 
Horses,  cats,  and  dogs  are  subject  to  fits, 


238 


A    DICTIONARY. 


which  often  depend  upon  an  accumulation 
of  water  in  the  ventricles  of  the  brain,  or 
upon  the  irritation  of  worms  in  the  stomach 
or  bowels.  During  the  present  year,  the 
author's  attention  was  called  to  a  horse, 
(the  property  of  jNIr.  Downs,  of  this  city ;) 
the  horse  was  lying  down,  and  at  times 
appeared  insensible  ;  convulsive  struggling 
would  take  place  occasionally.  The  mus- 
cles of  the  eye  were  affected  by  spasm,  and 
distorted ;  the  duration  of  the  fit  varied. 
As  the  disease  progressed,  the  hind  extremi- 
ties were  paralyzed,  and  the  horse  would 
struggle  violently  at  intervals  of  fifteen 
minutes.  On  an  examination,  after  death, 
nearly  a  peck-measure-full  of  the  long  round 
worm  was  found  in  the  small  intestines. 
The  author  examined  the  brain  of  a  horse 
that  was  said  to  die  in  a  fit,  and  found  about 
five  ounces  of  water  in  the  ventricles  of  the 
brain.  These  fits  in  horses  do  not  exactly 
resemble  those  occurring  in  man. 

Epistaxis.  —  Bleeding  at  the  nose.  This 
sometimes  occurs  in  glanders,  and  denotes 
a  considerable  idceration  within  the  nostrils. 
When  it  happens  to  a  horse  in  health,  it 
shows  an  vinequal  circulation  of  the  blood. 

Epsom  Salts.  —  Sulphate  of  magnesia. 
A  neutral  salt,  often  employed  as  an  aperi- 
ent for  cattle ;  but  it  is  very  uncertain  in 
horses,  and  is  apt  to  gripe  them. 

Eschar.  —  A  slough  formed  by  the  appli- 
cation of  caustic. 

Excrescence.— .- Any  preternatural  for- 
mation on  any  part  of  the  body,  as  warts, 
wens,  etc. 

Exostosis. —  An  osseous  tumor  originat- 
ing from  a  bone  ;  such  as  splent,  spavin, 
ringbone,  etc.  Perhaps  no  animal  is  more 
subject  to  this  disease  than  the  horse  ;  and 
in  no  department  of  the  veterinary  science 
is  there  a  greater  need  of  reform  than  in  the 
treatment  of  the  disease  now  under  con- 
sideration. Almost  every  man  who  knows 
anything  about  a  horse  can  detect  a 
spavin,  etc. ;  but  not  one  in  a  hundred  can 
tell  anything  about  the  true  nature  of  the 
malady,  or  the  indications  to  be  fulfilled  in 
the  treatment ;  and  in  consequence  of  a  lack 
of  knowledge  on  this  subject  many  a  poor 


animal  has  suffered  immensely,  who,  if  he 
was  not  deprived  of  the  power  of  speech, 
w^ould  make  the  cars  of  his  oppressors  tingle 
with  a  tale  of  man's  barbarity  and  inconsis- 
tency. 

The  bony  structure,  being  composed  of 
vital  solids,  although  studded  with  crystal- 
lizations of  saline  carbonates  and  phos- 
phates, is  liable,  like  other  parts  of  the  struc- 
ture, to  take  on  preternatural  or  morbid 
action,  and  may  result  from  or  accompany 
constitutional  idiosyncrasies,  resulting  from 
hereditary  taints  on  the  side  of  the  dam  or 
stallion.  The  most  frequent  causes  of 
splent,  spavin,  etc.,  are  undue  acts  of  exer- 
tion on  hard  pavements,  and  the  imposition 
of  weight  disproportioned  to  the  strength  of 
the  animal:  young  horses  are  particularly 
liable  to  exostosis  when  severely  worked  or 
over-burdened.  Any  sudden  or  extraordi- 
nary efforts  in  backing  or  suddenly  pulling 
up  at  full  speed,  racing  before  the  horse  shall 
have  arrived  at  maturity,  while  the  joints 
are  yet  in  a  state  of  imperfection,  very  fre- 
quently lay  the  foundation  of  exostosis. 
The  parts  being  sprained  and  taxed  beyond 
endurance,  disease  is  excited  in  the  liga- 
mentous substance,  and  extendsitself  to  the 
periosteum  and  bones  ;  the  ligaments  often 
become  ossified,  and  are  rendered  fixtures  ; 
the  periosteum,  being  raised  by  bony  ac- 
cumulations, presents  itself  in  the  situation 
of  splents,  spavin,  or  ringbone. 

Sir  A.  Cooper  divides  exostosis,  in  refer- 
ence to  its  seat,  into  two  kinds,  periosteal 
and  medullary ;  and  again,  as  to  its  nature, 
into  cartilaginous  and  fungous.  "  But," 
says  Mr.  Percivall,  "  it  is  to  that  kind  only 
which  is  situated  between  the  shell  of  the 
bone  and  the  periosteum  covering  it,  that 
we  have  to  attend  in  veterinary  practice. 
On  dissection  we  find  the  periosteum  thicker 
than  usual,  with  cartilage  beneath  it,  and 
ossific  matter  within  the  cartilage,  extend- 
ing from  the  shell  of  the  bone  nearly  to  the 
internal  surface  of  the  periosteum,  still 
leaving  on  the  surface  of  the  swelling  a  thin 
portion  of  cartilage  unossified." 

When  the  accretion  of  these  swellings 
ceases,  and  the  disease  has  been  of  long 


A   DICTIONARY. 


239 


standing,  they  are  found  to  consist  on  their  [  equalize  the  circulation,  and   excite  healthy 


exterior  surface,  of  a  shell  of  osseous  matter 
similar  to  that  of  the  original  bone ;  conse- 
quently, when  an  exostosis  has  been  formed 
in  the  manner  here  described,  the  shell  of 
the  original  bone  becomes  absorbed,  and 
cancelli  are  desposited  in  its  place. 

"  In  the  mean  time,  the  outer  surface  of 
the  exostosis  acquires  a  shell  resembling 
that  of  the  bone  itself.  When  the  exostosis 
has  been  steeped  in  an  acid,  and  by  this 
means  deprived  of  its  phosphate  of  lime, 
the  cartilaginous  structure  remains  of  the 
same  form  and  magnitude  as  the  diseased 
deposits ;  and,  as  far  as  I  have  been  able  to 
discover,  it  is  effused  precisely  in  the  same 
manner  as  healthy  bone. 
-  "  An  exostosis,  abstractedly  considered, 
does  not  appear  to  occasion  much  incon- 
venience to  the  animal,  except  in  the  early 
stages.  A  ringbone,  confined  to  the  pastern 
bones,  is  of  little  consideration  ;  but,  should 
it  show  itself  at  or  near  the  joint,  it  seldom 
fails  to  produce  lameness,  which  is  often  of 
a  permanent  nature.  Lameness,  therefore, 
is  not  an  invariable  symptom  of  exostosis ; 
for  most  splents,  and  many  ringbones,  and 
even  spavins,  exist  without  lameness. 
When  this  disease  invades  ligamentous 
structure,  however,  lameness  generally  ac- 
companies it,  —  an  effect  we  would  refer  to 
the  excessive  tenderness  of  the  part.  Should 
the  tumor  interfere,  either  from  its  bulk  or 
situation,  with  the  motions  of  joints,  mus- 
cles, or  tendons,  lameness  is  a  concomitant, 
and  often  irremediable,  symptom." 

It  appears  that  various  constitutional  and 
local  remedies  have  been  tried  for  the  pre- 
vention and  dispersion  of  exostosis,  viz., 
"  the  actual  cautery,  ammonia,  cantharides, 
caustic,  and  setons."  The  constitutional 
remedies  are  of  the  same  destructive  nature, 
and  have  but  too  often  aggravated  that 
which  they  were  intended  to  relieve  :  we  do 
not  believe  that  any  specific  treatment  has 
ever  had  the  honor  of  curing  these  forms  of 
disease ;  that  course  of  treatment  we  have 
ever  found  the  most  satisfactory  that  is  cal- 
culated to  promote  the  general  health  by 
sanative  means ;   we   cleanse   the   system, 


action  to  the  parts  by  stimulants  and  coun- 
ter-irritation (if  the  parts  are  inactive) ; 
poultices,  fomentations,  etc.,  if  there  is  pain, 
or  increased  action.  If  this  is  done  early, 
exostosis  is  easily  arrested,  unless  an  hered- 
itary taint  is  manifest. 

The  removal  of  exostosis  by  an  operation, 
we  are  told,  has  been  performed  with  suc- 
cess, and  no  doubt  there  are  cases  in  which 
it  may  safely  be  performed ;  yet  it  cannot 
be  successful  on  spavined  horses,  the  nat- 
ural termination  of  spavin  being  anchylosis 
of  the  bones  of  the  hock  and  inter-articular 
cartilage.  A  knowledge  of  this  fact  has  led 
men  to  suppose  that  Nature  has  turned  a 
summerset ;  and  they  endeavor  to  set  her 
right  with  the  firing  iron  and  the  imple- 
ments of  death ;  whereas,  if  her  intentions 
were  aided,  the  result  would  prove  more 
satisfactory. 

Extravasation.  —  The  escape  of  blood 
or  other  fluids  from  their  proper  vessels. 

Eye.  —  (See  part  first.) 

Falling  of  the  Yard  or  Penis.  —  This 
disease  sometimes  happens  to  horses  and 
bulls,  in  consequence  of  swelling,  excres- 
cence, and  ulceration  of  the  parts,  some- 
times of  an  obstinate  or  malignant  nature. 
It  may  also  be  occasioned  by  too  frequent 
sexual  intercourse.  It  may  also  depend  on 
weakness  of  the  part ;  and,  when  this  is  the 
case,  there  is  no  ulceration  nor  excrescence 
about  it.  If  it  depend  on  debility,  then 
tone  up  the  whole  animal,  and  wash  the 
parts,  first  with  castile  soap,  then  with  cold 
water.  If  it  result  from  ulceration,  wash 
with  weak  vinegar  and  water,  afterwards 
with  a  mixture  of  powdered  charcoal  and 
water.  The  latter  may  be  thrown  up  the 
sheath  with  a  common  syringe  or  injection 
pipe.  When  the  ulcers  show  a  disposition 
to  heal,  a  little  powdered  bayberry  bark 
will  generally  complete  the  cure.  When 
excrescences  form  on  the  sheath  or  inside 
of  it,  they  should  be  taken  off  by  applying 
a  ligature  tight  around  their  base. 

False  Quarter. — This  can  hardly  be 
considered  as  a  distinct  complaint,  but, 
more  properly,  as  a  consequence  resulting 


240 


A    DICTIONARY. 


from  some  one  of  the  former  diseases ;  in 
which,  from  the  injury  done  to  the  coronary 
vascular  ligament,  it  can  never  afterwards 
secrete  horn  ;  but  the  break  or  interruption, 
produced  by  the  interposition  of  a  portion 
of  non-secreting  substance,  causes  a  part  of 
the  outer  crust  of  the  wall  to  be  absent. 
Such  a  blemish  is  called  a  false  quarter ; 
and  it  is  evident  that  it  must  greatly  tend 
to  weaken  the  hoof.  It  likewise  sometimes 
produces  the  same  unpleasant  effects  as  a 
sand-crack,  by  the  separation  of  the  under 
layer  of  the  wall  admitting  the  vascular 
laminae  between  the  opening.  The  treat- 
ment can  be  only  palliative.  Keep  the  neigh- 
boring horn  always  thin :  use  a  bar  shoe, 
and  "  lay  off''"'  (as  a  smith  calls  it)  the  de- 
ficient quarter.  This  may  be  done  either 
by  paring  the  crust,  or  by  an  indentation  in 
the  shoe ;  the  choice  of  which  is  left  to  the 
prudence  of  the  operator,  with  this  excep- 
tion, that,  in  a  weak^thin  foot,  the  alteration 
should  always  be  made  in  the  shoe,  and  in 
a  strong  one,  in  the  crust. 

Farcy. —  A  disease  of  the  lymphatics  or 
absorbent  vessels.  Its  most  usual  form  is 
that  of  small  tumors,  or  huds^  as  they  are 
termed,  which  make  their  appearance  in 
different  parts  of  the  surface,  gradually  be- 
come soft,  or  suppurate,  and  burst,  and  be- 
come a  foul  ulcer.  Its  cause  may  be  found 
in  anything  that  will  derange  the  general 
system,  or  produce  debility ;  its  proximate 
cause  is  immoderate  work,  inattention  to 
diet,  hot  unhealthy  stables,  sudden  changes 
of  temperature,  standing  on  filthy  litter,  etc. 

Fauces.  —  That  j)art  of  the  throat  which 
lies  behind  the  tongue. 

Femoral  Artery. —  The  principal  ar- 
tery of  the  thigh. 

Femur,  or  Os  Femoris. —  The  thigli  bone. 

Fetlock.  —  A  lock  of  hair  at  the  lower 
part  of  the  fore  and  hind  legs. 

Fever  is  a  powerful  effort  of  the  vital 
principle  to  remove  all  obstructions  to  or- 
dinary and  proper  action.  The  reason  why 
veterinary  practitioners  have  not  ascertained 
this  fact  heretofore,  is,  because  they  have 
been  guided  by  the  false  principle  that  fever 
is  disease.     Let  them  bvit  receive  the  truth 


of  the  definition  we  have  given,  then  the 
light  will  begin  to  shine,  and  medical  dark- 
ness will  be  rendered  more  visible. 

Fever,  as  we  have  said,  is  an  effort  of  the 
vital  power  to  regain  its  equilibrium  of 
action  through  the  system,  and  should  never 
be  subdued  by  the  use  of  agents  that  de- 
prive the  organs  of  the  power  to  produce  it. 
Fever  will  be  generally  manifested  in  one 
or  more  of  that  combination  of  signs  com- 
monly given  as  a  description  of  fever,  viz : 
increased  velocity  of  the  pulse,  heat,  red- 
ness, pain  and  swelling,  thirst,  obstructed 
surface,  etc.,  some  of  which  will  be  present, 
local  or  general,  in  greater  or  less  degree,  in 
all  forms  of  disease.  In  what  is  called 
acute  attacks  these  signs  are  very  manifest : 
in  chronic  cases,  they  are  often  faint ;  but 
still  they  exist.  When  an  animal  has  taken 
cold,  and  there  is  power  enough  in  the  sys- 
tem to  keep  up  a  continual  Avarfare  against 
obstructions,  the  disturbance  of  vital  action 
being  unbroken,  the  fever  is  called  pure,  or 
unbroken.  The  powers  of  the  system  may 
become  exhausted  by  efforts  at  relief,  and 
the  fever  will  be  periodically  reduced :  this 
form  of  fever  is  called  remittent.  It  would 
be  as  absurd  to  expect  that  the  most  accu- 
rate definition  of  fever  would  correspond,  in 
all  its  details,  with  another  case,  as  to  ex- 
pect all  animals  to  be  alike. 

There  are  many  agents  that  obstruct 
vital  action,  and  many  an  organ  to  be 
obstructed,  which  some  have  classed  as  dis- 
tinct fevers ;  for  example,  milk  fever,  puer- 
peral fever,  symptomatic,  typhus,  inflamma- 
tory, etc.  Our  system  teaches  us  that  there 
is  but  one  cause  of  fever,  viz.,  the  natural 
motive  power  of  the  system,  and  but  one 
fever  itself,  viz.,  accumulated  vital  action ; 
hence  the  treatment  must  be  physiological. 

Veterinary  Surgeon  Percivall,in  an  article 
on  fever,  says :  "  We  have  no  more  reason, 
nor  not  near  so  much,  to  give  fever  a  habita- 
tion in  the  abdomen,  as  we  have  to  enthrone 
it  in  the  head ;  but  it  would  appear,  from 
the  full  range  of  observation,  that  no  part 
of  the  body  can  be  said  to  be  insusceptible 
of  inflammation  [local  fever]  in  human 
fever,  though,  at  the  same  time,  no  organ  is 


A  DICTIONARY. 


241 


invariably  or  exclusively  affected.  All  I 
wish  to  contend  for  is,  that  both  idiopathic 
and  symptomatic  fevers  exhibit  the  same 
form,  character,  and  species,  and  the  same 
general  means  of  cure ;  and  that,  were  it 
not  for  the  local  affection,  it  would  be 
difficult  or  impossible  to  distinguish  them. 
When  we  come  to  examine  the  accounts 
of  different  authors  on  fever,  and  compare 
them  one  with  another,  we  can  hardly  re- 
frain from  coming  to  the  conclusion  that 
their  descriptions  were  originally  derived 
from  human  medicine,  and  have  been  but 
variously  modified  to  suit  the  prevailing 
doctrines  of  the  day ;  they  have  gone  through 
a  system  of  imaginary  fevers,  and  regularly 
transferred  the  observations  and  language 
of  ancient  authors  upon  diseases  of  the 
human  species  to  the  constitution  of  quad- 
rupeds.'' 

In  the  treatment  of  disease,  and  when 
fever  is  present,  manifested  by  a  determina- 
tion of  blood  to  the  head,  the  object  is  to 
invite  the  blood  downward  and  outward; 
or,  in  other  words,  equalize  the  circulation 
by  warmth  and  moisture  externally,  as  in 
lockjaw. 

In  neat  cattle,  should  fever  be  present, 
the  eyes  appear  dull  and  watery,  the  muzzle 
dry,  and  rumination  has  ceased;  then  the 
blood,  for  want  of  room  in  the  nutritive  tis- 
sues, is  forced  upon  the  lungs,  liver,  spleen, 
brain,  or  other  glandular  tissues,  and  men 
have  named  the  disease  congestive  fever. 
The  author  advises  the  reader  not  to  feel 
alarmed  about  the  fever,  but  set  to  work 
and  relieve  the  congestion.  Disease  of  the 
bowels,  garget  of  the  teats  and  udder,  will 
require  fomentation  and  stimulants  to  the 
parts. 

Filly. —  A  name  given  to  a  mare  until 
she  is  two  or  three  years  old. 

Film.  —  Opacity  of  the  cornea. 

Filtration. —  Straining  liquids  through 
unsized  paper ;  also  through  sand  or  porous 
stone. 

Firing. —  A  severe  operation,  often  per- 
formed on  horses,  for  spavins,  curbs,  ring- 
bones, etc.  Such  barbarity  should  never  be 
practised :  it  is  a  disgrace  to  this  age  of  im- 

31 


provement.  When  discoveries  are  leaping 
on  discoveries,  and  medical  reform  has  ger- 
minated, shall  we  not  permit  the  poor  dumb 
brute  to  share  the  benefits  of  our  investiga- 
tion? Every  man  who  loves  a  horse,  or 
wishes  well  to  the  cause  of  horse-manity,  will 
say  that  a  more  safe  and  effectual  system  of 
veterinary  practice  is  necessary  to  rescue 
from  the  torture  of  the  firing  iron  one  of  the 
noblest  and  most  valuable  quadrupeds  in 
the  world. 

"  The  rage  of  firing  is  very  generally,  and 
much  too  frequently,  adopted,  and  no  doubt 
upon  most  occasions,  hurried  on  by  the 
pecuniary  propensity  and  dictation  of  the 
interested  operator,  anxious  to  display  his 
dexterity,  or,  as  Scrub  says,  'his  newest 
flourish '  in  the  operation ;  and  when  per- 
formed, and  the  horse  is  turned  out  to  grass, 
if  taken  up  sound,  I  shall  ever  attribute 
much  more  of  the  cure  to  that  grand  speci- 
fic, rest,  than  to  the  effects  of  his  fire." 
(See  Taplin's  Farriery,  p.  83.)  Hence  the 
firing  iron,  like  all  other  destructive  agents, 
excites  the  system  to  rally  her  powers  and 
resist  the  encroachments  of  disease ;  yet  the 
process  is  like  taking  a  citadel  by  storm ; 
the  breaches  that  are  made  by  the  weapons 
of  warfare  (such  as  the  firing  iron,  scalpel, 
lancet,  and  poison)  can  be  traced,  and  leave 
unmistakable  evidences  of  their  encroach- 
ments. Instead  of  provoking  the  vital 
powers  to  action  by  such  destructive  en- 
ginery, we  should  afford  Nature  all  the  aid 
we  can,  but  never  interfere  with  her  opera- 
tions. 

Fistula  op  the  Withers.  —  "An  ob- 
stinate disease  of  the  horse's  withers,  or 
points  of  the  shoulder,  commonly  produced 
by  a  bruise  of  the  saddle."  No  wonder 
Dr.  White  calls  it  "obstinate,"  when  the 
following  treatment  is  recommended  by 
him:  "The  scalding  mixture — it  consists 
of  any  fixed  oil  (as  lamp  or  train  oil),  spirit 
of  turpentine,  verdigris,  and  corrosive  sub- 
limate. These  are  put  into  an  iron  ladle, 
and  made  nearly  boiling  hot ;  and  in  this 
state  the  mixture  is  to  be  applied  to  the 
diseased  parts,  by  means  of  a  little  tow 
fastened  to  the  end  of  a  stick  !    It  is  neces- 


242 


A   DICTIONARY. 


sary  to  prevent  the  mixture  from  flowing 
over  the  sound  parts,  as  it  would  not  only 
take  off  the  hair,  but  cause  ulceration  of  the 
skin."  If  this  mixture  will  produce  diseased 
action  in  the  sound  parts,  we  need  not  ask 
what  will  be  the  result  when  applied  to 
parts  aheady  diseased.  The  author  has 
cured  many  cases  of  fistula,  by  treating 
them  as  common  abscesses,  with  the  appli- 
cation of  stimulating  antiseptic  and  tonic 
poultices  (see  Poultices),  and  by  a  puri- 
fying course  of  treatment,  with  proper 
attention  to  diet,  etc. 

Fleam.  —  An  instrument  with  which 
horses  and  cattle  are  bled. 

Flesh.  —  A  common  name  for  the  mus- 
cles of  the  body. 

Flexor. —  The  flexors  are  those  that 
bend  one  bone  upon  another.  The  tendons 
that  serve  to  bend  the  leg,  for  example,  are 
named  flexors. 

Foaling.  —  The  bringing  forth  young  in 
mares  is  not  so  often  attended  with  difliculty 
as  in  cows,  and  they  have  seldom  occasion 
for  assistance.  They  should  be  placed  in  a 
situation  where  they  may  have  shelter,  and 
where  they  are  free  from  danger. 

Fomentations.  —  Fomentations  are  gen- 
erally made  by  pouring  boihng  water  on 
camomiles,  burdock,  poplar  bark,  etc.  For 
an  emollient  fomentation,  ground  slippery 
elm  is  preferred.  In  inflammation  of  the 
bowels,  for  example,  the  parts  may  be 
fomented  with  flannels  wrung  out  in  a  thin 
mixture  of  sHppery  elm. 

Foot. —  (See  part  first.) 

Foot  Rot.  —  This  name  is  applied  to  a 
disease  in  the  feet  of  sheep.  This  disease 
often  happens  to  such  as  are  fed  in  low 
meadows,  or  where  the  grass  holds  the  frost 
or  cold  dews  for  a  considerable  time.  Prob- 
ably a  foul  habit  of  body  may  be  a  predis- 
posing cause.  In  the  treatment  of  foot  rot, 
we  should  endeavor  to  find  out  the  cause, 
or  causes,  of  the  disorder,  and  change  the 
food  or  location  of  the  sheep.  If  the  disease 
has  spread  under  the  horny  covering,  all  the 
superfluous  horn  should  be  carefully  pared 
away,  so  that  the  dressing  may  be  applied 
to  the  whole   of  the  affected  parts.     The 


dressing  is  composed  of  powdered  lobelia, 
formed  to  the  consistence  of  paste,  with 
honey. 

Foul  Feeders.  —  Horses  are  so  named 
that  have  depraved  or  vitiated  appetites, 
eating  foul  litter  and  earth  from  the  ground. 

Founder. — A  term  expressive  of  the  dif- 
ferent forms  of  rheumatism  and  ruin  in  the 
horse.  Veterinary  writers  describe  three  dif- 
ferent forms  of  this  disease,  viz.,  founder  of 
the  body,  chest,  and  feet.  This  is  one  and  the 
same  disease,  only  located  in  different  parts, 
and  may  arise  from  the  same  general  causes; 
which  consist  in  chiUing  the  animal  when 
exhausted,  by  which  means  the  perspiration 
is  obstructed,  by  much  fatigue,  and  by  vio- 
lent and  long-continued  exertion  :  exposing 
the  animal  to  cold  wind  or  rain,  or  washing 
his  legs  and  thighs,  and  sometimes  his  body, 
is  often  the  cause  of  founder.  Dr.  White 
calls  "  founder,  a  term  expressive  of  the 
ruined  state  of  the  horse."  And  well  he 
might  call  it  "  ruined."  How  many  thou- 
sand animals  have  been  ruined,  not  by  the 
disease,  but  by  the  treatment  I  Here  is  a 
specimen  of  it.  Dr.  White  says:  "The 
horse  was  bled  before  I  saw  him :  five  quarts 
of  blood  were  taken  off.  I  desired  he  might 
be  bled  again,  when  half  a  pailful  more  was 
abstracted.  In  less  than  an  hour  I  saw  him 
again,  and,  finding  that  he  was  not  relieved, 
took  another  half-pailful,  amounting  in  all 
to  four  gallons  !  The  horse  was  sent  home, 
and  seemed  to  be  doing  well  in  a  straw  yard, 
though  very  weak  and  thin.  [  No  wonder, 
after  such  a  loss  sustained  by  the  vital 
powers.  ]  At  the  end  of  three  or  four  months 
he  began  to  lose  his  fore  hoofs,  and,  after  de- 
clining some  time  longer,  he  died" — a 
victim  to  science.  It  is  evident,  from  expe- 
rience and  facts,  that  the  above  treatment 
renders  the  disease  incurable,  and  is  the  true 
cause  of  death ;  therefore,  not  suitable  to 
the  true  ends  to  be  accomplished.  What, 
then,  are  the  true  ends  to  be  accomplished  ? 
To  relax  muscular  structure,  determine 
action  to  the  surface,  improve  the  secretions, 
and  remove  obstructions  which  disturb  or 
repel  vital  action.  This  will  equalize  the 
circulation   of  the   blood,  when  it  will  be 


A   DICTIONARY. 


243 


found  that  there  will  he  no  necessity  for 
diminishing  its  quantity.  The  inflamma- 
tion, as  it  is  termed,  is  always  sufficiently 
controlled  when  the  circulation  of  the  blood 
is  free  and  universal.  Therefore,  instead  of 
withdrawing  vital  action,  promote  its  equal 
and  universal  diffusion. 

Frog.  —  The  posterior  part  of  the  horse's 
foot. 

Galbanum.  —  A  gum  resin,  sometimes 
employed  as  an  expectorant  and  anti-spas- 
modic ;  the  dose,  three  or  four  drachms.  It 
is  used,  also,  in  the  composition  of  warm 
adhesive  plasters,  such  as  gum  and  diachy- 
lon plaster. 

Gall.  —  A  common  name  for  bUe. 

Gall.  —  A  sore  produced  by  pressure,  or 
chafing,  of  the  saddle  or  harness. 

Gall  Bladder.  —  The  horse  has  no  gall 
bladder,  or  reservoir  for  bUe.  A  consider- 
able quantity  of  bile,  however,  is  formed  by 
the  horse's  liver,  and  is  conveyed  by  the 
hepatic  duct  into  the  first  intestine,  or  duo- 
denum. In  the  cow  and  sheep,  the  gall 
bladder  is  of  considerable  size. 

Ganglion.  —  This  term  is  applied  to  a 
natural  enlargement,  or  knot,  in  the  course 
of  some  of  the  nerves. 

Gangrene.  —  An  incipient  mortification. 
In  this  stage  of  the  disease,  there  is  gener- 
ally absence  of  pain ;  the  part  is  deprived 
of  vital  force,  by  causes  inducing  a  loss  of 
tone. 

Garlic.  —  It  operates  upon  the  horse  as 
a  diffusible  stimulant  and  expectorant ; 
possessing,  also,  diuretic  properties.  The 
author  considers  garlic  a  valuable  remedial 
agent  in  the  treatment  of  any  disease  where 
the  constitution  has  suffered  through  hard 
work,  or  ill  usage.  It  is  a  general  custom, 
on  the  eastern  coast  of  China,  to  allow  cattle 
to  eat  as  much  as  they  choose.  They  are 
never  known  to  suffer  any  inconvenience 
from  it ;  on  the  contrary,  they  appear  to 
thrive,  and  are  scarcely  if  ever  sick.  The 
only  objection  to  its  long-continued  use  in 
cattle  is,  that  it  imparts  an  unpleasant  flavor 
to  the  meat.  It  is  considered  by  Gibson  to 
be  a  valuable  remedy  in  coughs.  He  advises 
two  or  three  of  the  cloves  or  kernels,  cut 


small,  to  be  given  in  each  feed,  and  observes 
that,  by  continuing  this  practice,  with  right 
and  well-timed  exercise  and  careful  feeding, 
he  has  known  many  horses  to  recover,  even 
when  there  has  been  a  suspicion  of  their 
wind. 

Gastric  Juice. —  A  juice  formed  in  the 
stomach  for  the  purpose  of  digestion. 

Gastritis.  —  Inflammation  of  the  stom- 
ach. 

Gaunt-Bellied.  —  A  term  applied  to  a 
horse  when  he  is  drawn  up  in  the  flank. 

Gelatine.  —  A  component  part  of  ani- 
mal matter. 

Gelding.  —  A  castrated  horse.  Such 
horses  are  not  so  vigorous  as  stallions  ;  the 
latter  are  freer  from  disease  than  geldings, 
and  will  do  more  work,  and  keep  a  better 
appearance,  as  to  coat  and  flesh,  upon  the 
same  quantity  of  food. 

Gentian  Root.  —  A  good  tonic  for  a 
horse :  the  dose  is  two  or  three  drachms. 

Gestation. —  Being  with  young.  The 
time  of  gestation  in  the  mare  is  eleven 
months;  in  the  cow,  nine  months. 

Ginger.  —  An  aromatic  root,  possessing 
stimulant  and  carminative  properties. 

Glanders.  —  A  contagious  disease  pecu- 
liar to  the  horse,  the  ass,  and  the  mule. 
Many  persons  suppose  that  glanders  and 
farcy  are  the  effect  of  a  specific  poison  in 
the  blood  ;  but  this  theory  is  exploded. 
The  following  will  throw  some  light  on  the 
subject,  for  which  we  are  indebted  to  R. 
Vines,  V.  S. :  "  All  the  symptoms  of  disease 
which  constitute  glanders  and  farcy  invari- 
ably depend  on  the  unhealthy  state  of  the 
system  into  which  it  is  reduced  or  brought, 
and  not,  as  is  supposed,  from  a  specific 
poison  contained  in  the  blood ;  and  these 
symptoms  of  disease  are  found  to  depend 
on,  and  arise  from,  a  variety  of  causes; 
whether  they  occur  at  the  latter  states  or 
stages  of  common  inflammatory  diseases, 
such  as  strangles,  common  cold,  distemper, 
disease  of  the  lungs,  dropsy,  etc.,  or  whether 
they  arise  independently  of  such  causes ; 
for,  when  the  system  is  brought  into  an  un- 
healthy state,  and  is  more  or  less  debilitated, 
from  neglect,  or  by  the  improper  treatment 


244 


A   DICTIONARY. 


of  any  of  these  diseases,  [many  of  them  are 
improperly  treated],  farcy,  or  glanders,  is 
the  result.  The  disease  of  every  animal 
will,  therefore,  assume  a  character  accord- 
ing to  the  state  of  the  system."  Mr.  Perci- 
vall,  V.  S.,  says  :  "  The  state  of  the  body,  or 
constitution,  will  always  have  considerable 
influence  on  the  character  and  tendency  of 
disease.  In  horses  whose  bodies  are,  and 
have  long  been,  in  an  unthriving  and  un- 
healthy condition,  a  common  swollen  leg 
will  occasionally  run  into  farcy ;  and  a  com- 
mon cold  or  strangles,  or  an  attack  of  influ- 
enza, be  followed  by  glanders.  In  other 
cases,  such  unfortunate  sequels  will  super- 
vene without  any  ostensible  or  discoverable 
cause."  The  great  fault  of  those  who  have 
employed  their  talents  in  the  investigation 
of  the  subject  (glanders)  is,  that  they  take 
hold  of  the  wrong  end  of  it :  they  are 
engaged  in  attempting  to  discover  the 
"  specific  poison,"  where  none  exists,  when 
their  time  would  be  more  profitably  engaged 
in  studying  the  principles  of  a  system  of 
medication  that  would  rid  the  system  of 
these  early  exciting  causes,  viz.,  common 
colds,  etc.,  and  thus  prevent  this  great  bug- 
bear, glanders.  The  author  can  at  any 
time,  within  a  period  of  a  few  months,  and 
without  the  assistance  of  "  specific  poison," 
manufacture  a  case  of  genuine  glanders  out 
of  the  following  materials  :  A  horse  would 
be  selected  —  and  many  such  could  be  found 
in  the  city  of  Boston  —  whose  general  health 
shall  be  impaired ;  let  the  surface  be  ob- 
structed by  standing  in  a  shower  of  rain, 
without  anything  to  protect  the  animal 
from  the  pelting  storm  ;  then  put  him  into 
a  stall  near  the  door,  where  a  current  of 
cold  air  will  pass  the  hind  extremities  :  he 
remains  in  this  situation  during  the  night. 
On  the  following  morning,  the  animal  ap- 
pears dull,  and  is  off'  his  feed.  It  is  soon 
ascertained  that  he  has  taken  cold;  now 
treat  him  according  to  the  kiU-or-ciu"e  prac- 
tice :  "  If  there  is  difficulty  of  breathing,  and 
the  throat  is  sore,  —  or,  in  other  words,  the 
usual  symptoms,  —  the  fiirst  thing  to  be 
done  is,  to  bleed  largely,  until  the  horse 
faints.     He  should  then  be  put  into  a  cool 


place.  It  is  often  necessary  to  repeat  the 
bleeding  two  or  three  times.  If  the  throat  is 
very  sore,  blister  the  part."  (See  Canthar- 
iDEs.)  ^The  secretions  now  become  im- 
paired, there  is  loss  of  appetite,  the  coat 
stares  ;  there  is  a  dull,  sleepy  appearance 
about  the  animal ;  the  discharge  from  the 
nostrils  now  assumes  an  acrimonious  and 
putrid  character,  which,  acting  chemically 
on  the  membrane  of  the  nose,  constitutes 
ulceration :  the  latter  corrode  the  cartilage 
and  bones,  and  glanders  is  the  result.  Now 
we  will  view  it  in  another  form.  The  ani- 
mal has  taken  cold  (see  Catarrh)  ;  the 
lungs  —  from  previous  disease,  and  the  sub- 
sequent inhalation  of  impure  air  in  a  hot 
and  crowded  stable  —  are  incapacitated, 
and  their  power  to  purify  and  vitalize  the 
blood  is  destroyed;  hence  we  have  deposits 
of  morbific  matter  on  the  mucous  mem- 
brane, which  corrode,  ulcerate,  and  finally 
attack  the  substance  of  the  lungs,  and 
tubercle  is  the  result,  which  may  terminate 
in  glanders.  The  expectoration,  or  passage 
of  acrimonious  humors  through  the  nostril 
of  the  horse  from  the  lungs,  does,  in  its  pas- 
sage, irritate  the  schneiderian  membrane  at 
a  point  where  it  is  in  immediate  contact 
with  ossific  or  cartilaginous  structure,  and 
sufficiently  accounts  for  the  ulcers  found  in 
the  nostrils  in  the  above  case.  We  do  not 
hesitate  to  say  that  glanders  can  be  pro- 
duced without  infection,  or  contagion,  and 
that  a  common  cold  or  catarrh,  neglected  or 
improperly  treated,  will  often  terminate  in 
glanders.  IVIr.  Vines,  V.  S.,  states  "that 
the  practice  of  physicing  horses,  and  expos- 
ing them  to  wet  and  cold,  when  they  have 
common  catarrh,  will  produce  confirmed 
glanders." 

According  to  the  testimony  of  IVIr.  G. 
Fenwick,  V.  S.,  of  London,  "  Glanders  is 
a  symptom  of  tubercles  in  the  lungs  in  nine 
times  out  of  ten ; "  hence,  when  a  horse 
has  taken  cold,  and  the  surface  is  obstructed, 
the  prudent  owner  wiU  endeavor  to  force  a 
crisis ;  that  is,  to  open  the  pores  of  the  skin, 
and  promote  perspiration.  This  can  be 
done  by  the  use  of  warmth  and  moisture 
externally,  and  the  administration  of  warm, 


A   DICTIONAEY. 


245 


anti-spasmodic  drinks.  This  will  relieve 
the  stricture  of  the  surface,  and  permit  the 
egress  of  morbific  matter,  which  would 
otherwise  be  thrown  on  the  lungs,  or  kid- 
neys. If  there  is  not  sufficient  power  in 
the  system  to  determine  action  to  the  sur- 
face, then  administer  diffusible  stimulants. 
Mr.  Youatt  remarks :  "  Improper  stable 
management  is  a  more  frequent  cause  of 
glanders  than  contagion.  The  air  which  is 
necessary  to  respiration  is  changed  and  em- 
poisoned in  its  passage  through  the  lungs ; 
and  a  fresh  supply  is  necessary  for  the  sup- 
port of  life.  That  supply  may  be  sufficient 
barely  to  support  life,  but  not  to  prevent 
the  vitiated  air  from  again  and  again  pass- 
ing to  the  lungs,  and  producing  irritation 
and  disease.  The  membrane  of  the  nose, 
possessed  of  extreme  sensibility,  is  easily 
irritated  by  this  poison.  Professor  Cole- 
man relates  a  case  which  proves  to  demon- 
stration the  rapid  and  fatal  agency  of  this 
cause.  '  In  the  expedition  to  Quiberon,  the 
liorses  had  not  been  long  on  board  the 
transports,  before  it  became  necessary  to 
shut  down  the  hatchways  :  the  consequence 
of  this  was,  that  some  of  them  were  suffo- 
cated, and  that  all  the  rest  were  disem- 
barked either  glandered  or  farcied.  In  a 
close  stable,  the  air  is  not  only  vitiated  by 
breathing,  but  there  are  other  and  more 
powerful  sources  of  mischief.  The  dung 
and  the  urine  are  suffered  to  remain,  fer- 
menting and  giving  out  injurious  gases.' " 

Glands.  —  Soft,  spongy  substances  in 
various  parts  of  the  body,  which  serve  to 
secrete  particular  humors  from  the  blood. 
They  are  vulgarly  called  kernels. 

Gleet.  —  A  discharge  of  a  mucous  fluid 
from  the  urethra,  vagina,  or  nostrils. 

Glottis. —  The  upper  part  of  the  larynx, 
or  top  of  the  windpipe.  The  sensibility  of 
this  part  is  so  great,  that,  if  any  substance 
happen  to  fall  into  the  larynx,  the  most 
painful  and  distressing  symptoms  are  pro- 
duced ;  and,  unless  the  extraneous  matter  be 
expelled  by  coughing,  or  removed  by  an 
operation  (bronchotomy),  a  fatal  termina- 
tion will  be  the  consequence. 

Gorged.  —  A  term  applied  to  cattle  with 


an  overloaded  stomach. .  When  they  are  in 
this  state,  they  are  said  to  be  blasted,  blown, 
or  hoven ;  probably  from  the  quantity  of 
carbonic  acid  gas  that  is  generated,  and  by 
which  the  stomach  is  so  distended  that  cat- 
tle often  die  in  consequence  of  it.  When 
cattle  are  put  into  a  pasture,  which  abounds 
in  nutritious  food,  to  which  they  have  been 
unaccustomed,  or  have  an  improper  quan- 
tity given  them,  they  frequently  fill  the 
paunch  to  such  an  extent  that  they  are  in- 
capable of  ruminating :  hence,  the  food  re- 
maining in  a  warm  situation,  the  combined 
action  of  heat  and  moisture  generates  the  gas. 

Granulations. —  A  term  applied  to  the 
little,  red,  grain-like,  fleshy  bodies,  which 
arise  on  the  surface  of  ulcers  and  suppurat- 
ing sores.  Their  use  is  to  fill  up  cavities, 
and  approximate  the  sides. 

Grease.  —  A  swelling  of  the  horse's 
heels,  and  discharge  of  stinking  matter. 

Gripes.* — (See  Colic.) 

Gristle.  —  A  name  commonly  given  to 
cartilage.     (See  Cartilage.) 

Grogginess.  —  A  horse  is  said  to  be 
groggy,  when  he  has  a  tenderness,  or  stiff- 
ness, about  the  feet,  which  causes  him  to 
go  in  an  uneasy,  hobbling  manner. 

*  Scientific  Treatment  of  Colic,  or  Gripes.  — 
"  On  the  5th  Sept.,  1824,  a  young  bay  mare  was  admitted 
into  the  infirmary,  with  symptoms  of  colic,  for  which  she 
lost  eight  pounds  of  blood  before  she  came  in.  The  fol- 
lowing drench  was  prescribed  to  be  given  immediately  : 
laudanum  and  oil  of  turpentine,  of  each,  three  ounces, 
with  the  addition  of  six  ounces  of  decoction  of  aloes.  In 
the  course  of  half  an  hour  this  was  repeated  !  But,  shortly 
after,  she  vomited  the  greater  part  by  the  mouth  and  nos- 
tiils.  No  relief  having  been  obtained,  t^velve  pounds  of 
blood  were  taken  from  her,  and  the  same  drink  was  given. 
In  another  hour  this  drench  was  repeated ;  and  for  the 
fourth  time,  during  the  succeeding  hour ;  both  of  which, 
before  death,  she  rejected,  as  she  had  done  the  second 
drink.  Notwithstanding  these  active  measures  were 
promptly  taken,  she  died  about  thi-ee  hours  after  her  ad- 
mission." (See  Clarke's  Essay  on  Gripes.)  It  appears 
that  the  doctors  made  short  work  of  it.  Twelve  ounces 
of  laudanum,  and  the  same  of  turpentine,  in  three  hours ! 
But  this  is  secundum  artem.  This  is  called  skilful  treat- 
ment, and  justifiable  in  every  case  where  the  symptoms  are 
urgent. 

Had  the  relaxing  and  stimulating  plan,  practised  by  us, 
been  resorted  to,  and  in  a  proper  time  and  manner,  it 
would  probably  have  saved  the  poor  brute.  "We  have  at- 
tended a  large  number  of  the  same  sort  of  cases,  and  have 
not  yet  lost  the  first. 


246 


A   DICTIONARY. 


Gullet,  or  (Esophagus.  —  A  muscular 
and  membranous  tube,  by  which  the  food, 
etc.,  is  conveyed  from  the  mouth  to  the 
stomach.  The  upper  part,  or  funnel-like 
cavity,  is  named  pharynx.  The  gullet 
passes  down  the  neck  behind  the  windpipe, 
along  the  neck,  through  the  diaphragm,  and 
terminating  in  the  stomach. 

Gums. —  The  fleshy  parts  of  the  sockets 
of  the  teeth. 

Habit.  —  By  tliis  term  is  meant  the  dis- 
position, or  temperament,  of  the  body  or 
constitution,  whether  natural  or  acquired. 
The  term  habit  is  also  applied  to  any  vice, 
as  starting,  kicking,  rearing,  etc.  All  bad 
habits,  whether  of  the  body,  constitution, 
temper,  or  disposition  of  animals,  may  be 
in  some  measure  corrected,  if  not  entirely 
put  a  stop  to,  by  proper  attention  to  break- 
ing, breeding,  and  stable  management. 

Halter  Cast.  —  Owing  to  the  improper 
length  of  the  halter,  the  horse  is  apt  to  get 
his  fore  leg  across  it,  falls  down,  and  some- 
times injures  liimself  considerably. 

Ham.  —  This  is  the  name  given  to  the 
muscular  part  of  the  hind  leg,  terminating 
in  the  great  tendo  Achillis,  or  hamstring. 

Hand.  —  The  division  in  the  standard  for 
measuring  horses  is  thus  named.  A  hand 
is  four  inches. 

Haw. —  (See  Eye,  part  first,) 

Heart.  —  (See  part  first.) 

Heel.  —  A  term  applied  to  the  back  part 
of  the  termination  of  the  hoof. 

Hemlock. —  A  narcotic  vegetable  poison, 
deriving  its  deleterious  properties  from  an 
alkaline  principle,  called  conia.  It  has  been 
known  to  kill  many  horses  who  have  par- 
taken of  it. 

Hemorrhage. —  A  flow  of  blood  from 
any  part  of  the  body,  in  consequence  of 
the  rujiture  of  an  artery  or  vein.  Hemor- 
rhage, from  external  injury,  is  most  readily 
stopped  by  taking  up  the  bleeding  vessel, 
and  tying  it  with  saddler's  silk ;  but,  when 
this  cannot  be  done,  the  bleeding  may  gen- 
erally be  stopped  by  pressiu-e,  or  styptics. 

Hepatitis.  —  Inflammation  of  the  liver. 

Hide-Bound.  —  When  horses  are  out  of 
condition,  and  have  harsh  dry  coats,  the 


skin  will  be  contracted,  and  found  tight 
about  the  ribs.  It  is  a  symptom  of  disease, 
and  shows  that  the  general  health  is  im- 
paired. 

Hip-snoT,  —  This  is  known  by  one  of  the 
hip  bones  being  lower  than  the  other.  It 
generaUy  depends  on  a  fracture  of  the  os 
innominatum,  or  part  of  the  pelvis ;  the  part 
having  formed  an  irregular  kind  of  union, 
so  that  the  bone  on  that  side  is  shorter  than 
the  other. 

Hock. —  The  horse's  hock  is  composed 
of  six  bones.  These  bones  are  all  con- 
nected together  by  very  strong  ligaments, 
which  prevent  dislocation,  but  allow  a 
slight  degree  of  motion  among  them.  The 
surfaces  that  are  opposed  to  each  other 
are  thickly  covered  by  elastic  cartilage,  and 
by  a  membrane  secreting  the  synovia,  or 
oily  fluid,  which  guards  against  friction. 
These  bones  are  so  strongly  bound  together 
as  almost  to  defy  dislocation. 

Hoof-bound. —  A  dry,  brittle,  and  mor- 
bid state  of  the  foot.  A  want  of  vital 
action,  occasioned,  says  Dr.  White,  "by  in- 
flammation," which  he  calls  disease.  Now 
it  is  evident  that  no  vital  action,  as  that  of 
fever  and  inflammation,  can  be  properly 
termed  disease.  The  only  action  that  can 
be  properly  termed  disease,  is  the  chemical 
action  manifested  in  suppuration  and  gan- 
grene. This  is  the  great  popular  eiTor  that 
we  are  laboring  to  overcome.  It  is  that  of 
attributing  disease  and  death  to  the  action 
of  the  powers  of  life.  When  a  part  has  be- 
come diseased,  especially  the  foot  (for  from 
it  the  blood  has  a  kind  of  up-hill  work  to 
perform,  in  returning  to  the  heart  by  the 
veins),  there  is  a  low  state  of  vitality  ;  very 
little  can  be  accomplished  by  the  vital  pow- 
ers, amounting  only  to  a  low  form  of  in- 
flammation. And,  of  course,  the  chemical 
power  of  decomposition,  always  present 
and  never  tired,  gets  the  advantage  and 
decomposes  the  part ;  we  then  have  thrush, 
which,  if  improperly  treated,  the  hoof  falls 
off"  by  the  process  of  decomposition,  or,  in 
other  words,  mortification.  It  becomes  sep- 
arated from  the  living  parts,  for  want  of 
inflammation,    or    vital    supremacy,    over 


A   DICTIONARY. 


247 


chemical  agency ;  and  then  the  loss  of  the 
hoof  is  strangely  attributed  to  inflamma- 
tion, or  the  vital  power,  which  did  all  it 
could  to  prevent  such  a  termination. 

Hoof-Casting.  —  A  partial  or  complete 
separation  of  the  horse's  hoof  from  the  sen- 
sitive foot. 

HoosE. —  A  term  used  by  cow  doctors. 
It  signifies  a  cough,  either  chronic  or  acute, 
with  which  cattle  are  affected,  from  expos- 
ure to  cold  winds  or  rain. 

Ho  RE  HOUND. —  A  bitter  vegetable,  used 
in  horse  practice  as  a  tonic  and  expectorant. 

HovEN.  —  (See  Blasted.) 

Hydatid. —  A  thin  bladder,  containing  a 
fluid  resembling  water,  and  nearly  trans- 
parent. It  is  found  in  different  animals. 
In  sheep,  it  occasions  a  disease  named  gid, 
or  giddiness;  the  hydatid  being  found  in 
one  of  the  ventricles  of  the  brain,  or  in  its 
convolutions.  On  account  of  the  pressm-e 
it  makes  on  the  brain,  it  disturbs  the  func- 
tions of  that  important  organ,  especially 
when  the  sheep  are  hurried  or  driven. 

Hydrocele.  —  Dropsy  of  the  testicle  and 
its  appendages. 

Hydrophobia. —  Canine  madness. 

Hydrothorax,  or  Dropsy  of  the  Chest. 
—  Mr.  Percivall  informs  us,  "  that  the  ob- 
jects to  be  pursued  in  the  treatment  of 
hydrothorax  are  twofold :  first,  we  are  to 
diminish  any  excess  of  action  that  may 
show  itself  in  the  sanguineous  system,*  and 

*  In  plain  English,  abstract  blood.  This  not  only  di- 
minishes the  sanguineous  system,  but  every  other  function 
or  system.  The  regulars  have  tried  blood-letting  to  their 
hearts'  content;  their  patients  have  been  rowelled,  blis- 
tered, calomelized,  turpentinized,  and  hellebored,  yet  they 
have  never  been  able  to  preserve  life,  "except  two  solitary 
cases  in  Mr.  Sewell's  practice;  "  for  Mr.  Percival  tells  us, 
in  his  lectures,  that  "  he  never  saw  a  case  terminate  favor- 
ably." Is  not  this  a  proof  that  our  brethren  are  on  the 
wrong  track  ?  We  are  told  that  the  proximate  causes 
of  dropsy  are  "  debility  and  an  obstructed  perspiration ;  " 
and  that  it  may  result  from  "  loss  of  blood,  diarrhoea,  dia- 
betes, and  other  circumstances  that  rapidly  exhaust  the 
system."  Hence  the  processes  of  cure  are  just  the  means 
calculated  to  produce  the  disease.  The  true  indications 
in  the  treatment  are,  to  warm  and  relax  the  surface,  and 
promote  perspiration;  for  whatever  checks  it  stops  the 
egress  of  morbific  matter  from  the  system,  and,  of  course, 
determines  it  upon  the  internal  surfaces.  Diffusable  stim- 
ulants may  be  given,  to  keep  up  the  action  on  the  surface. 
The  general  health  must  be  improved. 


thereby  lessen  the  effusion  of  fluid  into  the 
chest ;  and  secondly,  by  increasing  the  ac- 
tion of  the  absorbent  system,  effect  the 
removal  of  what  is  already  accumulated."  * 
Most  surgeons  recommend  early  tapping  in 
dropsy.  The  operation  may  be  performed 
with  the  common  trocar  and  canula.  The 
best  place  for  the  introduction  of  the  instru- 
ment is  the  space  between  the  eighth  and 
ninth  ribs,  close  to  their  cartilages ;  not  be- 
tween the  latter,  lest  the  pericardium  be 
punctured.  Here,  making  the  skin  tense 
with  the  fingers  of  the  left  hand,  the  instru- 
ment, with  its  point  directed  upwards  and 
inwards,  may,  with  a  little  rotary  move- 
ment, gradually  be  thrust  in,  until  the  re- 
sistance to  its  entry  suddenly  ceases ;  when 
the  trocar  should  be  withdrawn,  and  the 
canula  at  the  same  time  pushed  onwards, 
lest  it  slip  out.  If  the  flow  of  water  sud- 
denly ceases,  a  small  whalebone  probe 
should  be  introduced  through  the  pipe. 

Ichor.  —  A  thin,  acrimonious  discharge 
from  ulcers,  or  diseased  parts. 

Icterus. — Jaundice,  or  yellows. 

Idiosyncrasy. —  A  peculiar  constitution, 
or  temperament. 

Ileum.  —  The  last  portion  of  the  small 
intestine.  It  terminates  in  the  large  intes- 
tine, or  blind  gut,  named  caecum. 

Imposthume. —  A  collection  of  matter,  or 
pus,  in  any  part. 

Incontinence  of  Urine.  —  A  continual 
dripping  of  the  m-ine  from  a  horse's  sheath. 

Inflammation.  —  Inflammation  and  fever 
are  one  and  the  same  thing.  When  fever 
is  confined  to  a  small  part,  it  is  called  in- 
flammation. (See  Inflammation,  part 
first.)  Dr.  White,  although  an  advocate  of 
the  popular  error,  viz.,  blood-letting,  makes 
some  very  sensible  remarks  on  the  subject. 
If   men    generally  would  carry  out   these 

*  The  action  of  the  absorbent  system  never  was,  nor 
never  can  be,  excited  when  the  lancet  is  cooperative.  Ab- 
sorption is  a  physiological  result,  and  cannot  be  excited  by 
agents  that  act  pathologically.  The  balance  between  ex- 
halation and  absorption  is  lost,  in  consequence  of  which, 
more  fluid  is  poured  out  than  is  taken  up :  hence,  if  we 
excite  the  cxhalents  to  throw  off  the  morbid  fluids  from 
the  surface,  there  will  be  less  for  the  absorbents  to  take  up, 
and  the  chances  of  success  will  be  greater. 


248 


A   DICTIONARY. 


principles,  they  would  prevent  a  great  loss 
of  property.  "  It  must  be  obvious,  that 
when  an  animal  is  laboring  under  general 
inflammation,  or  fever,  in  consequence  of 
a  suppression  of  the  natural  discharges, 
whether  it  be  perspkation,  urine,  or  dung,  he 
cannot  be  cured  merely  by  the  abstraction 
of  blood;  for,  however  large  the  quantity 
abstracted,  that  which  remains  will  be  im- 
pure, or  acrimonious,  and  unfit  for  carrying 
on  a  healthy  action.  It  is  absolutely  neces- 
sary to  restore  the  natural  discharges  by 
means  of  suitable  medicines,  unless  that  be 
effected  by  an  effort  of  nature,  which  is  not 
an  uncommon  occurrence,  especially  when 
the  animal  is  supplied  with  some  bland 
fluid,  such  as  bran  water,  or  thin  bran 
mashes.  The  morbid  matter  sometimes 
runs  off  by  the  nostrils,  sometimes  by  the 
kidneys  or  bowels,  and  sometimes  by  a  gen- 
eral relaxation  of  the  sldn,  and  the  body  is 
thus  restored  to  health."  From  the  above 
we  are  led  to  the  conclusion  that,  after  all, 
Nature  is  the  most  efficient  doctor,  and  that 
man  should  be  her  servant,  to  procure  what 
she  wants,  merely  to  be  used  in  her  own 
way. 

Influenza.  —  Epidemic  catarrh.  Ca- 
tarrhs, or  violent  colds,  attended  with  sore 
throat,  and  a  thin,  watery  discharge  from 
the  eyes  and  nose.  It  appears  to  be  infec- 
tious, seldom  making  its  appearance  with- 
out attacking  several  horses  in  the  same 
stable.  The  horse  should  subsist  on  warm 
gruel,  and  have  a  blanket  thrown  over  him, 
and  a  drink  of  hyssop  tea.  As  soon  as  the 
surface  of  the  body  is  relaxed,  and  becomes 
moist,  the  catarrh  will  disappear. 

Injection.  —  A  term  sometimes  applied 
to  clysters. 

Inosculation.  —  The  running  of  arteries 
and  veins  into  one  another,  or  the  inter- 
union  of  the  extremities  of  arteries  and 
veins. 

Inspiration.  —  The  act  of  drawing  air 
into  the  lungs. 

Integument.  —  Any  common  covering  of 
the  body  :  it  generally  includes  skin,  muscle, 
and  membrane. 

Intercostal. —  A  term   given   to  parts 


situated  between  the  ribs :  thus,  we  have 
intercostal  muscles,  etc. 

Intermittent.  —  A  name  given  to  dis- 
orders that  appear  to  go  off  at  certain  peri- 
ods, and  return  after  some  interval. 

Intestines.  —  The  horse's  intestines  are 
about  ninety  feet  in  length. 

Intus-susception.  —  This  is  occasioned 
by  one  portion  of  the  bowels  being  drawn 
within  the  other. 

Iris.  —  That  part  of  the  eye  by  which 
the  light  admitted  to  the  retina  is  regu- 
lated. 

Irritability. —  All  muscular  parts  pos- 
sess the  property  of  contracting,  or  shrink- 
ing, when  irritated,  and  are  therefore  en- 
dowed with  irritability. 

Issues.  —  (See  Rowels.) 

Itching.  —  Itching  in  horses  is  generally 
a  consequence  of  foul  feeding,  and  may  be 
occasioned  by  mange. 

Jaundice.  —  In  jaundice,  the  natural 
course  of  the  bile  is  perverted,  and  re-ab- 
sorbed into  the  circulation. 

Jaw-Locked. —  (See  Lockjaw.) 

Jejunum.  —  Part  of  the  small  intestine  is 
thus  named,  from  its  being  generally  found 
empty. 

Joints.  —  A  joint  is  formed,  generally 
speaking,  by  the  heads  of  two  or  more 
bones.  These  ends  are  covered  by  a  layer 
of  cartilage  or  gristle,  which  is  of  a  yielding 
nature.  There  is  formed  within  the  joint  a 
slippery  fluid,  called  synovia,  or  joint  oil. 
The  ends  of  the  bones,  thus  covered  with  a 
smooth,  yielding  surface,  so  slippery  that 
they  move  freely  on  each  other  without  suf- 
fering from  friction,  are  then  firmly  tied  to- 
gether by  a  strong  substance,  named  liga- 
ment, which  completely  surrounds  the  head 
of  the  bones  :  this  is  termed  capsular  liga- 
ment. In  some  joints  we  find  an  additional 
Hgament  within  the  capsular  ligament,  or 
cavity :  thus,  in  the  hip  joint,  a  strong  lig- 
ament connects  the  head  of  the  thigh  bone 
with  the  socket  that  receives  it. 

Joints  are  subject  to  disease,  either  from 
external  injury,  or  from  long-continued  ex- 
ertion of  them.  In  the  former,  the  capsular 
ligament  is  penetrated,  and  a  discharge  of 


A   DICTIONARY. 


249 


synovia  ensues.  Mr.  Percival  remarks 
"  that,  in  many  cases  of  open  joint  (com- 
monly called  so),  there  is  no  division  nor 
injury  whatever  of  the  capsular  ligament ; 
but  merely  the  exposure  of  some  bursa  mu- 
cosa placed  between  the  joint  and  the  ex- 
ternal wound :  the  discharge  is  of  the  same 
kind  as  in  the  former  case,  and  we  can  only 
determine  which  it  is  by  carefully  probing 
the  wound.  Most  of  all,  we  are  likely  to 
make  this  mistake  in  the  shoulder  joint  and 
hock,  when  heat  and  swelling  are  present. 
From  the  acute  sensibility  of  ligamentous 
parts  when  inflamed,  the  system  quickly, 
and  almost  invariably,  sympathizes ;  so  that, 
in  all  severe  cases  of  this  nature,  symptom- 
atic fever  supervenes,  the  pulse  becomes 
accelerated,  the  horse  heaves  at  the  flanks, 
refuses  his  food,  and  shows  symptoms  of 
the  most  affecting  suffering.  It  must  be 
borne  in  mind  that,  although  a  joint  be  not 
open  in  the  first  instance,  subsequent  slough- 
ing may  expose  its  cavity.  Now,  the  ordi- 
nary effects  of  disease  in  the  synovial 
membrane  are,  first,  a  preternatural  secre- 
tion of  synovia,  —  hence  the  profuse  dis- 
charge observed  in  these  cases ;  second,  an 
effusion  of  adhesive  matter  into  the  cavity 
of  the  joint;  third,  a  thickening  of  the 
synovial  membrane,  a  conversion  of  it  into 
a  substance  resembling  gristle,  and  an  effu- 
sion of  adhesive  matter,  and  probably 
serum,  into  the  cellular  substance  around, 
by  which  the  external  parts  and  those  of 
the  joints  are  firmly  cemented  together. 
In  the  latter  stage  the  disease  commonly 
extends  itself  to  the  cartilaginous  surfaces  ; 
they  exfoliate,  leaving  the  extremities  of  the 
bones  denuded,  to  grate  on  each  other  as 
often  as  the  joint  is  moved.  The  bones,  in 
their  turn,  throw  out  deposits  from  their 
ends  around  the  joint,  —  a  process  that  ulti- 
mately ensues,  and  anchylosis  is  the  result." 
The  indication  to  be  fulfilled  is  to  pro- 
mote adhesion  by  bringing  the  edges  to- 
gether and  confining  them  in  contact,  either 
by  taking  a  few  stitches,  or  shaving  the  hair 
off"  around  the  parts  and  applying  strips  of 
adhesive  plaster.  The  parts  may  have  a 
pledget  of  lint  bound  on,  moistened  with 

32 


healing  balsam  ;  and,  if  the  limb  will  admit 
of  it,  a  splint  may  be  bound  to  the  back  part 
of  it,  so  as  to  prevent  all  possibility  of  flex- 
ion. If  union  cannot  be  produced  by  this 
means,  the  parts  may  be  poulticed  with 
astringents.  The  object  is  to  close  the 
joint,  and  promote  granulation.  If  the 
parts  are  inactive,  sprinkle  the  surface  of 
the  poultice  with  charcoal  and  capsicum. 
In  a  case  that  came  under  the  author's 
care  in  this  city,  and  one  in  which  there 
was  no  hope  of  its  healing  by  the  first  in- 
tention, the  tincture  of  capsicum  was  daily 
injected :  this,  together  with  tonic,  stimulat- 
ing, astringent  poultices  and  fomentations, 
completed  the  cure.  In  cases  where  the  ex- 
ternal wound  is  large,  and  there  is  much 
heat,  pain,  and  loss  of  motion,  poultices  of 
a  relaxing  and  lubricating  nature  should  be 
used ;  such  are  lobelia  and  slippery  elm.  A 
severe  injury  of  this  kind  may  be  converted 
into  a  simple  wound  by  the  combined  influ- 
ence of  these  remedies.  The  horse  should 
be  kept  at  rest,  on  a  light  diet  of  scalded  food, 
and  an  occasional  dose  of  alterative  medi- 
cine. 

When  lameness  is  manifest  without  heat 
or  swelling,  and  there  is  reason  to  suppose 
that  the  animal  has  been  overworked,  rest 
and  proper  attention  to  diet  will  be  all  that 
is  necessary.  When  the  case  is  one  of  long 
standing,  a  run  at  grass  may  effect  a  cure, 
unless  there  is  reason  to  suppose  that  the 
articulatory  surfaces  of  the  bones  are  dis- 
eased; we  are  not  supposed  to  do  more 
for  these  subjects  than  alleviate  their  suf- 
ferings, or,  what  amounts  to  the  same  thing, 
diminish  their  lameness. 

Jugular  Veins.  —  The  large  veins  of  the 
neck,  where  a  horse  is  bled. 

Kernels.  —  A  common  name  for  glands  : 
thus,  the  parotid  glands,  situated  beneath 
the  ear,  are  termed  the  kernels  under  the 
ear. 

Kino.  —  An  astringent  gum  resin. 

Lacteals.  —  Absorbent  vessels,  which 
convey  the  chyle  from  the  bowels  into  the 
thoracic  duct. 

Lameness.  —  The  cause  of  lameness  in 
horses  is  often  very  obscure,  and  can  only 


260 


A    DICTIONARY. 


be  discovered  by  a  patient  and  careful  ex- 
amination. A  slight  degree  of  lameness 
often  passes  unnoticed ;  or,  if  it  be  observed, 
the  owner  too  often  persuades  himself  that 
it  will  pass  off.  It  is  always  the  most  pru- 
dent plan  to  lay  up  a  horse  the  moment  he 
is  observed  to  be  lame,  and  submit  to  the 
inconvenience  of  doing  without  his  services 
until  he  is  cured.  When  lameness  is  caused 
by  wounds  or  bruises,  the  injured  part  is 
generally  discovered  without  difficulty, 
though  pricking,  in  shoeing,  is  not  always 
so  easily  seen.  All  lameness  from  injuries 
within  the  hoof  is  often  detected  with  diffi- 
culty. Slight  lameness  is  most  readily  seen 
by  making  the  horse  trot  gently,  without 
giving  any  support  to  the  head  by  the  bridle 
or  halter,  and  without  urging  him  with  the 
whip  :  the  lameness  is  then  seen  by  his 
dropping  harder  and  dwelling  longer  on  the 
sound  leg  than  on  the  lame  one,  in  order  to 
favor  the  latter ;  and  this,  when  the  lame- 
ness is  at  all  considerable,  is  attended  with 
a  corresponding  motion  of  the  head,  which 
drops  a  little  whenever  he  steps  on  the  sound 
limb.  An  experienced  observer  can  at  any 
time  distinguish  lameness  merely  by  seeing 
a  horse  walk  out  of  the  stable.  It  often  hap- 
pens, in  very  severe  lameness  of  one  or  both 
fore  feet,  that  the  horse,  Avhen  led  out,  wiU 
appear  to  be  lame  in  the  hind  feet  also  :  this 
is  occasioned  by  the  animal  endeavoring  to 
favor  the  fore  foot  or  feet  by  throwing  the 
bulk  of  his  weight  on  the  hind  legs.  In  all 
cases  of  lameness,  unless  the  cause  is  so  evi- 
dent as  to  render  it  unnecessary,  it  is  proper 
to  examine  the  foot  carefully  in  the  first 
place  ;  and  it  should  never  be  forgotten  that 
swelling,  heat,  and  tenderness  of  the  fetlock 
joint,  or  even  the  leg,  may  arise  from  an  in- 
jury to  the  foot.  In  lameness  of  the  foot, 
the  affected  foot  wiU  be  warmer  than  the 
other.  Considerable  relief  may  almost 
always  be  afforded  in  foot  lameness  by  keep- 
ing the  feet  moist,  or  pasturing  the  animal 
in  soft  meadow  land,  or  by  stopping  the 
bottoms  of  the  feet  with  a  wet  sponge,  by 
paring  them  when  necessary.  "We  some- 
times find,  on  examining  a  lame  foot,  that 
there  is  an  enlargement  immediately  above 


the  coronet,  at  the  heels  and  quarters,  and  that 
this  enlargement  feels  hard  and  bony.  This 
is  termed  ossification  of  the  lateral  carti- 
lages ;  it  is  more  distinctly  seen  by  compar- 
ing it  with  a  sound  foot.  In  lameness  of 
the  foot,  there  is  sometimes  a  crack  in  the 
horn  towards  the  heels,  extending  from  the 
coronet  a  little  way  down  the  hoof:  this 
happens  sometimes  after  a  horse  has  been 
travelling.  This  is  named  a  sand-crack. 
When  the  seat  of  lameness  is  in  the  fetlock 
joint,  some  degree  of  heat  or  swelling  will 
be  perceived.  As  the  horse  stands,  he  will 
be  observed  to  favor  the  joint.  Lameness 
of  the  back,  sinews,  or  flexor  tendons  of  the 
leg,  is  easily  perceived  by  the  heat  and  ten- 
derness of  the  part. 

Lampas.  —  A  swelling  and  sometimes  ten- 
derness of  the  roof  of  the  mouth,  adjoining 
the  front  teeth.  When  the  part  is  tender, 
and  prevents  the  horse  from  feeding,  he 
should  be  fed  on  scalded  shorts  for  a  few 
days  ;  during  that  time,  the  mouth  may  be 
washed  twice  a  day  with  an  infusion  of 
powdered  bayberry  bark.  Two  ounces  of 
bark  may  be  infused  in  one  quart  of  boiling 
water :  after  macerating  for  one  hour,  it  will 
be  fit  for  use. 

Larynx.  —  The  upper  part  of  the  trachea 
or  windpipe. 

Lax.  —  (See  Scouring.) 

Laxative.  —  Medicines  that  purge  gen- 
tly ;  the  most  simple  and  safe  is  aloes. 

Ligaments  are  strong,  elastic  membranes, 
connecting  the  extremities  of  the  movable 
bones. 

Ligature.  —  Twine,  thread,  or  sUlc, 
waxed,  for  the  purpose  of  tying  arteries, 
veins,  or  other  parts. 

Lights.  —  A  common  name  for  lungs. 

Lily.  —  The  root  of  the  white  lily  is  fre- 
quently used  for  poulticing. 

Linseed,  or  Flaxseed.  —  An  excellent 
emollient  drink  is  made  by  pouring  two 
quarts  of  boiling  water  on  four  ounces  of 
linseed,  and  suffering  it  to  stand  in  a  warm 
place  for  a  short  time.  It  is  useful  in  cold, 
catarrh,  and  in  diseases  of  the  kidneys  or 
bladder. 

Liquorice.  —  The  root,  dried  and  pow- 


A   DICTIONARY. 


251 


dered,  is  used  for  the  same  purpose  as  the 
last  article. 

Lobe. —  A  portion  of  the  lungs  and  liver 
is  thus  named. 

Lockjaw. —  This  disease  is  too  well 
known  to  require  a  particular  description. 
It  is  evidently  a  disease  of  the  spinal  sys- 
tem,—  other  parts  becoming  sympatheti- 
cally affected,  —  and  often  arises  from  a 
wound  of  a  tendon,  or  nerve  :  it  occasion- 
ally follows  nicking,  or  docking.  Mr.  You- 
att  tells  us,  "  This  is  one  of  the  most  fatal 
diseases  to  which  the  horse  is  subject." 
For  the  information  of  our  readers,  we  wiU 
detaU  the  treatment  recommended  by  the 
above  author.  We  presume  that  every  man 
of  common  sense  will  come  to  the  conclu- 
sion that  the  disease  could  not  be  otherwise 
than  fatal  under  such  unwarrantable  bar- 
barity. We  have  no  personal  disrespect  for 
Mr.  Youatt.  It  is  the  system  of  treatment 
recommended  by  him  that  we  war  against ; 
a  system  that  has  kiUed  more  than  it  ever 
cured.  Mr.  Youatt  observes :  "  The  rational 
method  of  cure  would  seem  to  be,  first  to 
remove  the  local  cause  ;  but  this  will  seldom 
avail  much.  The  irritation  has  become 
general,  and  the  spasmodic  action  constitu- 
tional. The  habit  is  formed  and  will  con- 
tinue. It  will,  however,  be  prudent  to  en- 
deavor to  discover  the  local  cause.  If  it  be 
a  wound  in  the  foot,  let  it  be  touched  with 
the  hot  iron,  or  caustic,  and  kept  open  with 
digestive  ointment.  If  it  follows  nicking, 
let  the  incision  be  made  deeper,  and  stimu- 
lated by  digestive  ointment ;  and,  if  it  arise 
from  docking,  let  the  operation  be  repeated 
higher.*      In    treating    the    constitutional 

*  "First,  to  remove  the  local  cause;  but  this  will  sel- 
dom avail  much."  Then  why  torture  the  poor  brute? 
We  need  not  trouble  ourselves  about  the  particular  nerve 
affected  to  enable  us  to  relieve  a  sympathetic  disease, 
when  we  have  a  medicine  —  lobelia  and  milkweed,  orLidian 
hemp  —  that  will  relax  every  nerve  in  the  animal.  "  If  it 
be  a  wound  in  the  foot,  let  it  be  touched  with  the  hot  iron." 
This  is  a  means  better  calculated  to  injure  than  relieve. 
"We  should  apply,  at  once,  the  means  that  are  known  to 
act  on  the  whole  nervous  structure.  "  If  it  follows  nick- 
ing, let  the  incision  be  made  deeper  ;  and  if  it  arise  from 
docking,  let  the  operation  be  repeated  higher."  What 
beautiful  philosophy  this  is!  —  make  one  disease  to  cure 
another.     Is  it  strange  that  "  this  is  one  of  the  most  fatal 


disease,  efforts  must  be  made  to  tranquillize 
the  system  ;  and  the  most  powerful  agent  is 
bleeding.  [Yes,  most  powerful  to  kill.] 
Twenty  pounds  of  blood  may  be  taken  away 
with  manifest  advantage.  There  is  not  a 
more  powerful  means  of  allaying  general 
hritation  ;  the  next  thing  is  to  resort  to  phy- 
sic. Here  again  that  physic  is  best  which 
is  speediest  in  its  operation  ;  the  Croton  nut 
has  no  rival  in  this  respect;  the  first  dose 
should  be  half  a  drachm,  and  the  medicine 
repeated  every  six  hours,  in  doses  of  ten 
grains,  until  it  operates.*  The  bowels,  in 
all  these  nervous  affections,  are  very  torpid. 

"  Then,  as  it  is  a  diseased  action  of  the 
nerves,  proceeding  from  the  spinal  marrow, 
the  whole  of  the  spine  should  be  blistered 
three  or  four  inches  wide.  (See  Canthar- 
iDEs.)  Having  bled  largely,  and  physiced, 
and  blistered,  we  seek  for  other  means  to 
lull  the  irritation  ;  and  we  have  one  at  hand, 
small  in  buht  and  potent  in  energy, — 
opium  !  f  Give  at  once  a  quarter  of  an 
ounce,  and  an  additional  drachm  every  six 
hours." 

The  best  method  we  know  of,  in  the 
treatment  of  lockjaw,  is,  first,  to  apply  a 
poultice  to  the  foot  (if  it  has  been  wounded), 
consisting  of  about  six  ounces  of  lobelia, 
four   ounces  of   slippery  elm,  two   ounces 

diseases  1 "  Is  it  not  a  wonder  that  any  live  1  Must  not 
their  escape  be  attributed  to  the  conservative  power  of  the 
system,  in  spite  of  the  violence  done  1  AVhen  Mr.  Youatt 
recommends  cutting  the  tail  a  little  higher,  to  cure  a  dis- 
ease that  was  produced  by  the  same  operation,  —  viz., 
docking,  —  he  puts  the  author  in  mind  of  the  man  who 
filed  the  edge  of  his  razor  to  sharpen  it. 

*  In  the  first  part  of  this  paragraph,  Sir.  Youatt  ob- 
serves, "the  most  powerful  agent  to  tranquillize  the  sys- 
tem is  bleeding."  So  say  the  butchers  when  they  bleed 
the  ox,  and  conduct  the  process  till  no  blood  remains. 

t  This  is  a  narcotic,  vegetable  poison,  and,  although  large 
quantities  have  been  occasionally  given  to  the  horse  vnth- 
out  apparent  injury,  experience  teaches  us  that  poisons 
in  general  —  notwithstanding  the  various  modes  of  their 
action,  and  the  difference  in  then*  symptoms  —  all  agree  in 
the  abstraction  of  vitality  from  the  system.  Dr.  Eberle 
says,  "  Opiates  never  fail  to  operate  perniciously  on  the 
whole  organization."  Dr.  Gallup  says  :  "  The  practice  of 
using  opiates  to  mitigate  pain  is  greatly  to  be  deprecated. 
It  is  probable  that  opium  and  its  preparations  have  done 
seven  times  the  injury  that  they  have  rendered  benefit  on 
the  great  scale  of  the  civilized  world.  Opium  is  the  most 
destructive  of  all  narcotics." 


252 


A  DICTIONARY. 


of  capsicum,  powdered ;  mix  them  with  a 
suitable  quantity  of  meal  sufficient  for  two 
poultices,  which  should  be  renewed  every 
twelve  hours.  After  the  second  application 
examine  the  foot,  and,  if  suppuration  has 
taken  place,  and  the  matter  can  be  felt,  or 
seen,  a  small  puncture  may  be  made,  taking 
care  not  to  let  the  instrument  penetrate 
beyond  the  bony  part  of  the  hoof.  Next 
stimulate  the  surface  to  action,  by  warmth 
and  moisture,  as  follows :  take  about  two 
quarts  of  vinegar,  into  which  stir  a  handful 
of  lobelia;  have  a  hot  brick  ready  {the 
animal  having  a  large  cloth,  or  blanket, 
thrown  around  him),  pour  the  mixture  gradu- 
ally on  the  brick,  which  is  held  over  a 
bucket  to  prevent  waste ;  the  steam  arising 
will  relax  the  surface.  After  repeating  the 
operation,  apply  the  following  mixture 
around  the  jaws,  back,  and  extremities : 
chloroform,  and  olive  oil,  equal  parts  ;  rub 
the  mixture  well  in  with  a  coarse  sponge  ; 
this  will  relax  the  jaws  a  trifle,  so  that  the 
animal  can  manage  to  suck  up  thin  gruel, 
which  may  be  given  warm,  in  any  quantity. 
This  process  must  be  persevered  in ;  al- 
though it  may  not  succeed  in  every  case, 
yet  it  will  be  more  satisfactory  than  the 
blood-letting  and  poisoning  system.  No 
medicine  is  necessary  ;  the  gruel  will  soften 
the  faeces  sufficiently ;  if  the  rectum  is 
loaded  with  faeces,  give  injections  of  an  in- 
fusion of  lobelia. 

Lumbar  Muscles. —  Muscles  of  the  loins 
within  the  body,  and  in  the  region  of  the 
kidneys.  These  muscles  are  sometimes  in- 
jured by  violent  exertions,  and  the  kidneys 
often  participate  in  the  injury. 

Lungs,  or  Lights. —  The  organ  of  res- 
piration.    (See  Respiration,  part  first.) 

Luxation.  —  A  partial  displacement  of 
the  bones  forming  a  joint. 

Lymph. —  (See  Blood.) 

Lymphatics. —  (See  part  first.) 

Macreation  implies  soaking  or  steeping 
any  substance  in  water,  or  other  fluids,  so 
as  to  soften,  dissolve,  or  separate  it  from 
some  other  parts  with  which  it  is  combined. 

]VL\llenders. —  A  scurvy  kind  of  eruption 
on  the  back  part  or  bend  of  the  knee  joint. 


Mange.  —  A  disease  which  manifests  it- 
self in  the  skin,  and  causes  a  horse  to  be 
perpetually  rubbing  himself.  Cattle,  sheep, 
and  dogs  are  also  subject  to  mange.  It  is 
a  well  known  fact,  that  horses  are  very  apt 
to  become  mangy,  if  kept  long  in  the  stable 
without  grooming ;  yet  the  disease  may 
arise  from  causes  independent  of  a  neg- 
lected skin,  though  it  seldom  attacks  a  well- 
cleansed  animal.  Mr.  Percivall  observes : 
"  It  seems  that  mange  may  be  generated 
either  from  immediate  excitement  to  the 
skin  itself,  or  through  the  medium  of  that 
sympathetic  influence  which  is  known  to 
exist  between  the  skin  and  the  organs  of 
digestion.  We  have,  it  appears  to  me,  an 
excellent  illustration  of  this  in  the  case  of 
mange  supervening  upon  poverty, —  a  fact 
too  notorious  to  be  disputed,  though  there 
may  be  different  ways  of  theorizing  upon 
it." 

Mr.  Blaine  says,  "  Mange  has  three 
origins  —  filth,  debility,  and  contagion." 

Owners  of  horses  must  bear  in  mind,  that 
mange  can  be  communicated  by  the  brush 
or  comb  used  about  a  mangy  subject ;  the 
pustules  on  the  surface  contain  acari  or 
nites.  The  author  has  been  very  success- 
ful in  the  treatment  of  this  disease,  by  the 
daily  use  of  sulphur  and  soda. 

Marasmus. —  A  decay  or  wasting  of  the 
whole  body. 

Marsh  Mallows. —  A  plant  used  for 
making  emollient  drinks  and  fomentations. 

Mash. —  A  mash  is  made  by  pom-ing 
boifing  water  on  bran,  or  shorts,  then  cov- 
ering the  bucket  until  sufficiently  cool  for 
use.  Mashes  are  excellent  for  sick  and 
convalescent  horses,  and  such  as  have  not 
sufficient  exercise  to  keep  them  in  health. 

Masseter. —  The  name  of  a  muscle  of 
the  cheek,  by  which  mastication  is  per- 
formed. 

Mastication. —  (See  part  first.) 

Materia  Medica.  —  A  catalogue  and 
description  of  the  various  articles  used  in 
medicine. 

Maxilla.  —  The  jaw. 

Maxillary.  —  Belonging  to  the  jaw;  as 
the   maxillary   arteries   and   glands.      The 


A   DICTIONARY. 


253 


glands  under  the  jaw  are  named  sub-max- 
illary glands. 

Mediastinum.  —  A  duplicature  of  the 
membrane,  named  pleura,  by  which  the 
cavity  of  the  chest  is  divided  into  two 
parts. 

Medicine.  —  Mr.  Clark,  veterinary  sur- 
geon of  Edinburgh,  says :  "  Medicine  is  often 
given  to  the  poor  brutes  unnecessarily,  and, 
of  course,  mischievously.  If  a  man,  or 
horse,  be  in  a  state  of  health,  what  more  is 
required,  or  how  can  they  be  rendered  bet- 
ter ?  Health  is  the  more  proper  state  of 
the  animal  body,  and  it  is  not  in  the  power 
of  medicine  to  make  it  better,  or  to  preserve 
it  in  the  same  stated 

Dr.  White  says  :  "  The  custom  of  giving 
medicines  too  frequently,  is  a  bad  one  ;  the 
constitution  adapts  itself  to  it,  which  cir- 
cumstance renders  medicine  inefficacious 
when  necessary,  or,  at  least,  it  greatly  re- 
duces the  effects." 

If  a  horse  is  in  health,  the  proper  way  to 
promote  it  is  to  proportion  the  food  to  the 
labor. 

Dr.  White  continues :  "  Medicines  are 
given  to  the  horse  under  the  title  of  alter- 
atives. These  alteratives  are  composed  of 
antimony,  mercury,  sulphur,  nitre,  aloes, 
salts  "  {generally  altering  bad  for  worse). 

Mr.  Clark  says,  "  That  sulphur  not  only 
opens  the  body,  but  the  skin  also,  and  there- 
fore should  be  used  with  caution,  as  horses 
are  very  apt  to  catch  cold  on  too  liberal  a 
use  of  it." 

Salts  bring  on  great  sickness,  and  some- 
times violent  purging,  and,  instead  of  pro- 
moting the  secretions,  occasion  great  dryness 
of  the  skin. 

"  Aloes  given  in  small  quantities,  by  way 
of  alteratives,  and  too  frequently  repeated, 
weaken  the  stomach,  so  as  to  bring  on  a 
lax,  or  what  is  called  a  washy,  habit  of 
body. 

"Antimony  should  always  be  rejected,  if 
coarse  and  black,  like  gunpowder."  (See 
White's  Farriery,  p.  559.) 

The  above  author  says  :  "  It  is  amazing 
what  different  kinds  of  trash  are  forced  down 


horses'  throats.  The  following  is  a  striking 
instance :  A  gentleman,  in  London,  was 
greatly  prejudiced  in  favor  of  vinegar,  as  a 
cure  in  many  diseases.  His  favorite  horse 
was  taken  ill  in  very  warm  weather,  and, 
as  he  thought  vinegar  was  a  cooling  ardcle, 
he  ordered  a  pint  to  be  given  to  his  horse  at 
once.  It  was  no  sooner  given,  than  the 
horse  lay  down,  stretched  himself  out,  and 
died." 

Medulla  Oblongata. —  The  commence- 
ment of  the  spinal  marrow,  within  the  cra- 
nium. 

Membrane,  Mucous.  —  This  membrane 
is  folded  into  all  the  orilices  of  the  animal, 
as  the  mouth,  eyes,  nose,  ears,  lungs,  intes- 
tines, bladder,  etc. ;  in  fact,  into  every  cavity 
that  has  a  direct  communication  with  the 
external  surface.  Its  structure  of  arterial 
capillaries,  venous  radicles,  nervous  projec- 
tions, etc.,  is  similar  to  the  skin,  and  is 
considered  a  duplicate  of  the  external  sur- 
face. Its  most  extensive  surfaces  are  those 
of  the  lungs  and  intestines.  This  mem- 
brane furnishes  from  the  blood  a  fluid  called 
mucus,  to  lubricate  its  own  surface,  and 
protect  it  from  the  action  of  materials  taken 
into  the  system.  The  sldn  and  mucous 
membrane  are  a  counterpart  of  each  other. 
If  the  action  of  the  skin  is  suppressed,  the 
mucous  membrane  performs  a  part  of  its 
office  ;  thus,  a  cold,  which  closes  the  pores 
of  the  skin,  stops  perspiration,  which  is  now 
forced  through  the  membrane,  producing 
discharges  at  the  nose,  eyes,  etc. 

Serous  MEMBRANE.-Of  this  kind  are 
the  pleura  and  peritoneum  :  they  are  dis- 
tributed in  all  parts  of  the  system,  lining 
muscles,  tendons,  and  tendinous  sheaths, 
the  ends  of  movable  bones,  etc. ;  in  short, 
wherever  there  is  need  of  the  protection  of 
parts  against  friction.  They  secrete  from 
the  blood  a  fluid  called  serum,  for  the  pur- 
pose of  affording  this  protection.  The 
excessive  discharge  of  fluids  into  cavities 
lined  by  serous  membrane,  constitutes  the 
different  forms  of  dropsy.  There  are  other 
membranes,  viz.,  adipose,  which  secrete  the 
fat  of  the   body;    synovial,  which  secrete 


254 


A   DICTIONARF. 


synovia,  or  joint  oU;  and  cellular  mem- 
brane, or  tissue,  is  the  common  connecting 
substance  of  most  parts  of  the  body. 

Mesentery.  —  A  thin  membrane  by 
which  the  bowels  are  held  together,  and 
over  wldch  the  lacteals,  or  chyle  vessels, 
pass.  Besides  the  chyle  vessels,  there  are 
considerable  veins  and  arteries  passing  over 
the  mesentery.  The  arteries  are  distributed 
to  the  bowels,  and  the  veins  terminate  in 
the  vena  porta,  or  great  vein  of  the  liver. 

Metacarpus.  —  The  metacarpus  of  the 
horse  consists  of  one  great  bone,  commonly 
named  the  canon,  shank  bone,  or  fore  leg, 
and  tw'O  small  bones,  or  splent  bones,  at- 
tached by  ligaments  to  the  back  part  of  the 
canon  bone,  rather  towards  the  sides.  The 
suspensory  ligament  passes  down  on  the 
back  part  of  the  canon  bone,  and  between 
the  two  splents.  The  flexor  tendons,  or  back 
sinews,  pass  down  over  the  suspensory  lig- 
ament. When  the  bones  only  of  the  fore 
leg  are  spoken  of,  they  are  termed  meta- 
carpus. They  begin  at  the  knee,  and  end 
at  the  fetlock  joint. 

Metatarsus.  —  The  hind  leg,  between 
the  hock  and  fetlock  joints. 

Metatarsal  Bones.  —  The  hind  canon, 
or  shank  bone,  wdth  the  two  small  splent 
bones  attached  to  it.  The  large  blood- 
vessels and  nerves,  in  this  situation,  are  also 
named  metatarsal. 

Miasmata.  —  Poisonous  effluvia. 

Midriff. —  (See  Diaphragm.) 

Molares.  —  The  name  of  the  grinding 
teeth. 

Molten  Grease.  —  A  name  which  Mr. 
Blaine  has  given  to  dysentery. 

Morbid  Displacements  of  the  Intes- 
tines, etc  —  Rupture^  or  Intestinal  Hernia* 
Hernia,  in  its  strict  sense,  is  a  protrusion  of 
any  viscus  out  of  its  natural  cavity ;  hence 
we  have  hernia  of  the  brain,  of  the  lungs, 
and  of  the  various  viscera  of  the  abdomi- 
nal regions.  Hernia,  as  we  propose  to 
consider  it,  is  a  displacement  of  the  intes- 
tines from  the  abdominal  cavity,  either 
through  some  of  the  natural  openings,  or 

*  "Blaine's  Outlines,"  by  Mahew. 


through  artificial  ones,  the  effects  of  acci- 
dent. When  such  protrusion  takes  place 
through  a  moderate  opening,  and  the  por- 
tion of  gut  can  be  readily  returned,  it  is 
called  a  reducible  hernia ;  but  Avhen  it  oc- 
curs through  a  small  opening,  and  the  in- 
testine cannot  be  replaced,  it  is  termed  an 
irreducible  hernia.  If  the  mouth  of  the 
opening,  round  the  intestine,  constringe, 
and  prevent  the  return  of  the  bowel,  it  then 
forms  a  strangulated  hernia,  and  usually 
proves  fatal,  unless  relief  be  promptly  ob- 
tained. 

The  hernia,  by  far  the  most  common  in 
the  horse,  is  the  inguinal,  of  which  the 
scrotal,  or  when  the  bowel  descends  into 
the  scrotum,  is  most  frequently  observed  in 
the  stallion.  Bubonocele,  or  that  of  the 
groin,  is  a  very  rare  form  of  disease,  but  it 
is  occasionally  witnessed  in  geldings.  In 
the  former,  the  intestine  accompanies  the 
spermatic  cord  by  the  inguinal  canal 
through  the  abdominal  rings  into  the  scro- 
tum :  in  the  latter,  the  bowel  alone  lodges 
in  the  groin.  The  ruptures  we  have  named 
may  be  considered  as  the  only  ones  com- 
mon to  the  horse.  Some  of  them  are  very 
rarely  seen :  hernia  is  more  frequently  on 
the  right  than  on  the  left  side  ;  and  scarcely 
ever  appears  in  mares.  However,  ventral 
hernia,  or  rupture  of  the  muscles  of  the 
abdominal  sides,  and  protrusion  beneath 
the  skin  of  a  portion  of  intestine,  is  some- 
times beheld  in  either  sex,  and  perhaps,  of 
the  two,  is  more  frequently  witnessed  in 
the  female. 

The  causes  which  produce  hernia  are 
various,  but  all  arise  from  violence  of  exer- 
tion, or  the  effects  consequent  upon  external 
injuries.  With  us  the  cflbrts  used  in  racing, 
and  the  leaps  taken  in  hunting,  are  causes, 
as  we  may  readily  suppose  ;  when  we  con- 
sider that  the  dilatation  of  the  abdomen, 
restrained  as  it  is  by  weight  and  tight  girth- 
ings,  must  press  backwards  the  intestinal 
mass.  Rearing  and  kicking  also,  and  being 
cast  for  operations,  particularly  the  rising 
up  after  castration,  have  all  brought  it  on. 
Blows  with  a  thick  stick,  or  from  the  horn 
of  a  cow,  may  likewise  induce  it. 


A   DICTIONARY. 


255 


The  symptoms  of  strangulated  hernia  are 
very  similar  to  those  of  acute  enteritis  : 
there  is  the  same  uneasiness,  shifting  of 
position,  getting  up  and  lying  down  again. 
The  horse  rolls  in  the  same  manner,  and  in 
turninar  on  his  back  sometimes  seems  to 
get  a  momentary  respite  from  pain  ;  yet  it 
is  but  momentary,  for  the  suffering  is  not 
one  of  remission ;  it  is  constant ;  this  will 
serve  as  one  distinguishing  mark  betw"een 
it  and  spasmodic  colic,  with  which  it  has 
been  confounded.  In  stallions,  a  pathog- 
nomonic symptom  is,  that  the  testicle  on 
the  hernial  side  is  drawn  up  to  the  abdo- 
men, and  is  retained  there,  with  only  mo- 
mentary fits  of  relaxation ;  toward  the  last, 
the  pulse  is  quick  and  wiry ;  the  horse 
paws,  looks  at  his  flanks,  but  seldom  kicks 
at  his  belly.  We  assure  ourselves  of  her- 
nia by  an  oblong  tumor  in  the  groin,  of 
larger  or  smaller  bulk ;  hard  or  soft,  as  it 
may  contain  either  faeces  or  gas,  in  which 
latter  case  it  will  also  be  elastic.  When 
the  tumor  is  raised  by  the  hand,  or  pressed, 
a  gurgling  sound  is  emitted  ;  or,  if  the  horse 
be  coughed,  it  will  be  sensibly  increased  in 
dimensions. 

The  treatment  of  strangulated  hernia. — 
The  horse  suffering  under  the  affection  we 
will  suppose  to  be  a  stallion,  and  then  de- 
scribe the  various  manipulations  for  his 
relief :  firstly,  the  examination  into  the  state 
of  the  hernia ;  secondly,  the  application  of 
means  preparatory  to  the  application  of 
pressure ;  thirdly,  the  application  of  pres- 
sure itself;  also,  the  operation  of  removing 
the  stricture ;  and,  likewise,  the  application 
of  the  various  processes  to  hernia  in  the 
horse. 

The  treatment  of  hernia  in  a  stallion.  — 
First,  the  examination  of  the  hernial  sac. 
In  this  manipulation  both  hands  are  em- 
ployed ;  one  is  introduced  into  the  rectum, 
the  other  into  the  sheath.  The  one  within 
the  rectum  must  seek  the  internal  ring; 
while  the  other,  pursuing  the  course  of  the 
cord  on  the  side  affected,  is  to  be  pushed  up 
to  the  external  ring ;  and  thus,  in  the  nat- 
ural state,  the  opposed  fingers  may  be  made 
nearly  to  meet,  and  so  estimate  the  size  of 


the  opening.  However  small  the  protruded 
portion  of  gut,  the  practitioner  will  be  able 
to  detect,  and  even  to  reduce  it.  This  ex- 
ploration may  be  made  in  the  standing  pos- 
ture; but  it  will  be  conducted  with  more 
facility  and  certainty  if  the  animal  be  cast^ 
luhich  is  the  preferable  mode  of  proceeding. 

Secondly,  the  application  of  means  pre- 
paratory to  the  taxis :  these  are  said  to  be 
bleeding,  and  partially  paralyzing  the  parts 
by  administration  of  cliloroform  ;  or  lessen- 
ing the  volume  of  distention  by  dashing 
the  part  with  cold  water ;  or,  if  the  horse 
be  already  cast,  by  spreading  ice  over  the 
beUy. 

Thirdly,  the  manual  efforts  to  return  the 
displaced  gut.  To  fulfil  this  indication,  we 
are,  with  the  same  hope,  at  once  to  proceed 
thus:  The  horse  is  to  be  tin-own  upon  the 
opposite  side  to  that  disordered  ;  and,  after 
one  hind  leg  has  been  drawn  and  fixed  for- 
ward, as  for  castration,  he  is  to  be  turned 
upon  his  back,  and  in  that  position  main- 
tained by  trusses  of  straw,  whUe  other 
trusses  are  placed  under  Mm  to  raise  the 
croup.  With  both  arms  well  oUed,  or  cov- 
ered with  some  mucilaginous  decoction, 
the  operator  will  now  commence  his  explo- 
ration, taking  the  precaution  of  emptying 
the  rectum  as  he  proceeds.  As  soon  as  he 
shall  have  ascertained  that  it  is  a  case  of 
hernia, — have  assured  himself  the  gut  pro- 
truded through  the  ring  is  undergoing 
neither  stricture  nor  strangulation, — he  may 
endeavor  to  disengage  the  hernial  part,  by 
softly  drawing  it  inward  within  the  cavity, 
at  the  same  time  pushing  it  in  the  like 
direction  with  the  hand  within  the  sheath. 
Should  he  experience  much  difficulty  in 
these  attempts,  he  is  to  desist ;  violence 
being  too  often  the  forerunner  of  strangu- 
lation and  gangrene.  He  must  bear  in 
mind,  also,  that,  although  the  reduction  is 
effected,  unless  it  be  followed  by  immediate 
castration,  it  does  not  always  prove  to  be  a 
cure  :  the  protrusion  recurs  after  a  time, 
and  occasionally  even  the  moment  the  ani- 
mal has  risen.  If  the  taxis  should  be  fortu- 
nate enough  to  reduce  the  hernia,  and  it  be 
not  intended  to  castrate  the  horse,  apply  a 


256 


A   DICTIONARY. 


well-wadded  pledget,  or  folded  cloth,  to  the 
part ;  this  may  be  retained  with  a  bandage 
crossed  between  the  legs  from  side  to  side, 
and  fastened  by  one  part  under  the  belly  to 
a  girth  ;  and  also  passing  between  the  legs, 
it  may  be  again  made  fast  to  the  back  por- 
tion of  the  same  girth ;  the  intention  of 
this  is,  to  prevent  the  protrusion  of  the 
gut  by  the  exertion  of  rising,  and  conse- 
quently it  should  be  removed  as  soon  as 
that  danger  is  over.  If  a  radical  cure  were 
attempted,  of  course  the  clams  would  su- 
persede this,  either  in  the  stallion  or  gelding. 

And  concerning  the  treatment  of  strangu- 
lated hernia  in  geldings.  Liguinal  hernia, 
taking  the  same  course,  is  susceptible  of 
the  same  terminations,  and  requires  the 
same  treatment  as  in  stallions.  The  taxis 
is  to  be  employed,  and  will  be  used  with 
most  effect,  the  operator  (the  horse  lying 
upon  his  back)  extending  the  hernial  sheath 
with  one  hand,  while  he  manipulates  with 
the  other ;  or,  should  this  fail,  by  instructing 
his  assistant  to  hold  up  the  hernial  mass 
from  the  belly,  so  as  to  take  its  pressure  off 
the  ring,  and  thus  give  him  an  opportunity 
to  renew  his  efforts  with  more  effect.  In 
some  cases,  the  introduction  of  one  hand 
into  the  rectum  becomes  necessary.  The 
reduction  of  the  hernia  should  be  followed 
up  immediately  by  the  application  of  the 
clams,  if  we  unite  with  the  reduction  an 
attempt  at  permanent  cure  of  the  hernia ; 
taking  care,  at  the  time,  to  draw  out  the 
part  of  the  scrotum  to  which  the  vaginal 
sheath  is  adherent,  and  to  push  up  the 
clams  as  close  as  possible  to  the  belly  ;  they 
are  then  to  be  closed,  as  for  castration. 

Of  congenital  hernia,  our  limits  allow  of 
little  more  than  the  mention;  nor  need 
more  be  detailed,  as  its  consequences  are 
seldom  injurious.  It  appears  that  inguinal 
hernia  commonly  exists  in  the  fcetus  in 
utero.  M.  Lineguard,  V.  S.,  of  Normandy, 
where  breeding  is  very  extensively  pursued, 
has  ascertained  that  enterocele  is  invariably 
present  at  birth ;  even  in  abortions,  and  in 
subjects  still-born.  The  congenital  enter- 
ocele is  an  attendant  on  birth,  increasing  up 
to  the  third  or  sixth  month,  but  afterwards 


diminishing,  and  ultimately  vanishing. 
Should  it  continue  beyond  a  year  or  eight- 
een months,  it  is  to  be  regarded  as  a  clironic 
or  permanent  hernia.  Chronic  or  perma- 
nent hernia,  it  may  be  remarked,  our  obser- 
vations being  so  much  limited  to  geldings, 
we  see  little  of  Castration,  however,  with 
the  armed  clams,  is  the  evident  cure. 

Strangulation  of  the  Intestines,  or  Morbid 
Displacement  of  the  Intestines.  The  intes- 
tines, in  consequence  of  their  peristaltic 
motion,  become  sometimes  entangled  to- 
gether, and  a  fatal  strangulation  takes  place; 
this  happens,  occasionally,  from  some  of 
the  mesenteric  folds  entwining  them ;  some- 
times by  their  rupturing  the  mesentery,  and 
becoming  strangulated  by  passing  through 
the  opening  they  have  made  :  but  it  is  much 
oftener  the  consequence  of  spasmodic  ac- 
tion, and  during  colic  these  inversions,  invo- 
lutions, invaginations,  and  introsusceptions 
occur.  When  thus  affected,  it  is  not  un- 
usual for  the  ileum  to  become  reversed  in 
its  usual  course  ;  in  which  case,  a  portion, 
then  contracted  by  spasm,  becomes  forced 
into  a  part  less  constringed,  and  an  impen- 
etrable obstruction  thence  is  formed.  We 
may  draw  a  practical  inference  from  these 
cases,  —  that  in  spasm  we  should  attempt 
an  early  relief ;  and  likewise  that  we  should 
endeavor,  in  all  cases  of  failure  in  bowel 
affections, invariably  to  make  ^post-mortem 
examination :  and  this  we  may  do  on  the 
ground  that  repeated  cases  may  enable  us 
accurately  to  interpret  symptoms  ;  then,  al- 
though we  cannot  relieve,  we  may  offer 
such  an  opinion  as  will  convince  our  em- 
ployers it  is  not  our  ignorance  of  the  signs, 
but  our  circumscribed  means,  which  is  the 
cause  of  our  inability  to  afford  assistance.* 

Mortification.  —  A  part  deprived  of 
vital  force,  by  causes  inducing  a  loss  of  tone. 

Moulting. —  Casting  the  coat.  In  spring 
the  old  coat  is  shed,  or  thrown  off,  and  the 
horse  gradually  improves  in  spirit  and  in 
appearance ;  but,  during  the  change,  he  is 
more  liable  to  take  cold.  In  the  latter  part 
of  the  year,  the  coat  becomes  longer  d.nd 

*  Blaines'  "  Outlines." 


A  DICTIONARY. 


257 


coarser,  and  loses  its  healthy  gloss  ;  at  the 
same  time,  the  horse  often  becomes  weak, 
sweats  readily  upon  moderate  exercise,  and 
is  often  incapable  of  performing  his  usual 
labor.  This  is  more  especially  the  case 
with  horses  that  have  been  hard  worked 
and  badly  fed.  At  both  these  periods  it  is 
necessary  to  take  particular  care  of  horses, 
and  work  them  moderately.  A  horse,  when 
moulting,  should  not  be  exposed  in  the 
stable  to  a  current  of  air,  but  kept  in  a  ven- 
tilated stable.     Warm  clothing  is  improper. 

Mucilage.  —  A  solution  of  gum,  or  any- 
thing that  partakes  of  the  nature  of  gum. 
Gummy  or  mucilaginous  drinks  are  useful 
in  internal  disease ;  the  cheapest  is  an  in- 
fusion of  linseed  or  marsh-mallows ;  but  the 
best,  perhaps,  is  a  solution  of  gum  arable. 

Mucous  Membranes. —  (See  Membrane.) 

Mucous. —  Many  of  the  secretions  of  the 
body  are  of  a  mucous  nature. 

Mucus.  —  A  fluid  secreted  by  mucous 
surfaces. 

Muscle.  —  The  parts  that  are  usually  in- 
cluded under  this  name  consist  of  distinct 
portions  of  flesh,  susceptible  of  contraction 
and  relaxation. 

Musk.  —  A  powerful  odorous  substance, 
whose  medical  virtues  are  chiefly  anti-spas- 
modic. 

Myrrh.  —  A  gum  resin  of  a  fragrant 
smell  and  bitter  taste.  It  is  given  internally, 
as  a  tonic,  in  doses  of  one  or  two  drachms. 
Tincture  of  myrrh  is  sometimes  applied  to 
wounds,  ulcers,  and  sinuses. 

Nag.  —  A  name  sometimes  applied  to 
road  horses,  and  such  as  have  been  docked, 
in  contradistinction  to  those  that  have  long 
tails,  or  are  used  in  harness. 

Narcotics.  —  Medicines  which  stupefy, 
relieve  pain,  and  promote  sleep.  There 
are,  however,  two  different  ways  to  effect 
these  objects,  and,  of  course,  two  different 
characters  of  remedies  to  be  used  for  the 
purpose.  The  popular  method  is  to  ad- 
minister opium,  whose  natural  tendency  is 
to  depress  the  vital  powers,  and  deprive 
them  of  sensibility.  All  mixtures,  in  any 
form,  that  contain  opium,  though  soothing 
for  the  present,  are  ultimately  and    surely 

33 


pernicious.  The  true  plan  is  to  give  anti- 
spasmodics.    (See  Anti-spasmodics.) 

Nares.  —  The  nostrils. 

Necrosis.  —  The  mortification  and  sepa- 
ration of  a  portion  of  dead  bone  from  the 
other  parts  of  the  bone. 

Nephritics. —  Medicines  that  act  on  the 
kidneys. 

Nerving,  Nerve  Operation.  —  It  con- 
sists of  cutting  out  a  portion  of  the  nerve 
which  supplies  the  foot,  either  just  above 
the  fetlock  joint,  which  is  named  the  high 
operation,  or  in  the  pastern,  which  is  called 
the  low  operation.  In  the  former  the  sen- 
sibility of  the  foot  is  supposed  to  be  entirely 
desti-oyed,  and  in  the  latter  only  partly  so. 
Dr.  White  observes,  serious  mischief,  such 
as  the  loss  of  the  hoof,  has  sometimes  fol- 
lowed the  liigher  nerve  operation. 

"  After  the  division  of  a  nerve,  the  ex- 
tremities of  the  divided  portion  retract, 
become  enlarged  and  more  vascular;  but 
especially  the  upper  portion;  and  coagu- 
lable  lymph  is  effused,  which  soon  becomes 
vascular.  In  a  few  days  the  coagulable 
lymph  from  each  portion  becomes  united, 
and  anastomosis  forms  between  the  blood- 
vessels ;  the  lymph  gradually  assumes  a 
firmer  texture,  and  the  number  of  the  blood- 
vessels diminishes,  and  the  newly-formed 
substance  appears  to  contract,  like  all  other 
cicatrices,  so  as  to  bring  the  extremities  of 
the  divided  portions  nearer  and  nearer  to 
each  other.  It  is  difficult  to  determine, 
from  an  experiment  on  the  limb  of  an 
animal,  the  exact  time  at  which  the  nerve 
again  performs  its  functions  after  being 
divided.  In  eight  weeks  after  the  division 
of  the  sciatic  nerve,  I  have  observed  a  rab- 
bit to  be  in  some  degree  improved  in  the 
use  of  its  leg ;  but  at  the  end  of  eighteen 
weeks  it  was  not  perfect.  When  the  nerves 
of  the  leg  of  a  horse  are  divided  just  above 
the  foot,  they  are  sufficiently  restored  to 
perform  their  functions,  in  some  degree,  in 
six  or  eight  weeks  ;  but  it  must  be  observed 
that  these  nerves  are  only  formed  for  sensa- 
tion^ and  it  is  very  different  with  the  nerves 
of  nutrition,  voluntary  motion,  etc.;  the  re- 
union is  sometimes  accomplished  by  gran- 


258 


A    DICTIONARY. 


Illations.  Secondly,  I  would  observe,  that 
punctures  and  partial  divisions  of  nerves 
heal  in  the  same  way  as  when  there  has 
been  a  total  division ;  and  that,  even  on 
the  first  infliction  of  the  wounds,  the  func- 
tion of  the  nerves  is  very  little  impaired." 
(See  Swan's  work  on  morbid  local  affec- 
tions.) 

Mr.  Sewell  finds  "  that,  in  cases  of  entire 
section  of  a  nerve,  sensation  returns  in 
about  two  months ;  but  in  others,  in  which 
a  portion  of  nerve  has  been  exercised,  that 
the  period  of  restoring  feeling  can  by  no 
means  be  foretold :  in  one  of  his  own 
horses,  he  ascertained  that  there  was  no 
sensibility  in  the  foot,  even  at  the  expiration 
of  three  years ;  and  in  some  others,  after  a 
longer  interval,  the  organ  appeared  to  be 
wholly  destitute  of  feeling." 

Nicking. —  An  operation  often  performed 
on  horses,  to  raise  the  tail,  and  make  them 
carry  it  more  gracefully,  or  rather  to  suit 
the  taste  of  man. 

Nippers. —  The  front  teeth,  above  and 
below,  have  been  thus  named. 

Nitre.  —  IVIr.  Morton  writes  :  "  Nitre 
given  internally  is  a  febrifuge  and  diuretic. 
The  dose  is  from  two  to  four  drachms.  In 
order  to  obtain  its  full  effect  as  a  febrifuge, 
it  should  be  exhibited  in  the  form  of  ball,  so 
that  it  may  undergo  solution  in  the  stom- 
ach ;  but  as  a  diuretic,  it  is  best  given  in 
solution.  It  passes  to  the  kidneys  un- 
changed, and  its  presence  may  be  readily 
detected  in  the  urine  by  means  of  bibulous 
paper  immersed  in  it,  which,  on  being 
dried,  deflagrates ;  or,  if  the  quantity  given 
be  great,  it  may  be  procured  in  crystals 
from  the  urine.  Very  large  doses  of  this 
salt  act  as  an  irritating  poison.  Two 
pounds  being  given  in  sbc  pints  of  water  to 
a  horse,  apparently  in  health,  within  half  an 
hour  irritation  of  the  mucous  lining  of  the 
alimentary  canal  began,  evidenced  by  the 
faeces  being  voided  frequently  and  in  small 
quantities.  The  kidneys  were  soon  after 
excited  into  increased  action,  the  urine  being 
forcibly  expelled,  and  the  act  accompanied 
with  uneasiness.  In  about  four  hours  after, 
the  pulse  had  risen  to   nearly  double   the 


number  of  beats,  and  the  visible  mucous 
membranes  were  highly  injected.  Blood 
being  withdrawn  from  the  jugular  vein,  it 
presented  all  the  appearances  of  arterial 
blood.  In  the  serum  the  existence  of  the 
salt  could  be  detected,  but  it  was  obtained 
in  abundance  from  the  urine.  From  this 
period  the  symptoms  became  less  urgent, 
and  the  pulse  gradually  regained  its  healthy 
standard;  but  the  dung  and  urine  continued 
to  be  passed  more  frequently  than  natural 
throughout  the  day. 

Externally  a]:)pMed,  nitrate  of  potassa  is  a 
valuable  stimulant  to  wounds,  and  it  may 
be  employed  with  much  benefit  when  gan- 
grene has  taken  place.  For  this  purpose, 
a  saturated  solution  is  ordered  to  be  kept  in 
the  pharmacy. 

Oats.  —  According  to  Sir  H.  Davy's 
analysis,  oats  contain  742  parts  of  nutritive 
matter  out  of  1000,  which  is  composed  of 
641  mucilage,  or  starch,  15  saccharine 
matter,  and  87  gluten,  or  albumen.  New 
oats  are  difficult  of  digestion. 

Oblique  Muscles. —  The  muscles  of 
the  abdomen,  or  belly,  are  thus  named. 
There  are  four  of  them ;  two  external  and 
two  internal.  Some  of  the  muscles  of  the 
eye  are  also  named  oblique  muscles. 

Occiput. —  The  back  part  of  the  head. 

CEdema.  —  A  watery  or  dropsical  swell- 
ing. 

CEsoPHAGus,  or  Esophagus. —  The  tube 
passing  from  the  mouth  to  the  stomach. 

Ointments. —  Unctuous  substances  of 
the  consistence  of  butter ;  when  made  con- 
siderably thinner  by  the  addition  of  oil, 
they  are  termed  liniments ;  but  when  their 
solidity  is  increased  by  wax,  rosin,  etc., 
they  are  termed  plasters. 

Olecranon.  —  The  head  of  the  bone 
named  ulnar  (see  cut),  in  the  horse ;  it 
affords  a  powerful  lever  for  the  triceps  ex- 
tensor cubiti  muscle  to  act  upon,  in  straight- 
ening the  fore  arm  upon  the  humerus. 
(See  Skeleton.) 

Olfactory  Nerves  are  spread  over  all 
the  interior  of  the  nostril,  and  constitute 
the  sense  of  smell. 

Omentum.  —  The  omentum,  or  caul,  is  a 


A   DICTIONARY. 


259 


double  membrane,  containing  witliin  its 
folds  a  considerable  quantity  of  fat,  in  the 
human  body  and  many  animals.  But  in 
the  horse  this  is  never  seen ;  nor  does  the 
omentum  contain  much  fat ;  what  there  is 
lies  in  the  region  of  the  stomach. 

Opacity. —  A  want  of  transparency  in 
those  parts  of  the  eye  named  pupil,  or 
cornea. 

OPERATIONS. 

Op  surgical  operations,*  and  the  vari- 
ous RESTRAINTS  IT  IS  SOMETIMES  NECESSARY 
TO  PLACE  THE  HORSE  UNDER  FOR  THEIR  PER- 
FORMANCE.—  "  When  it  is  necessary  to  per- 
form any  painful  operation  on  so  powerful 
an  animal  as  the  horse,  it  is  of  consequence 
to  subject  him  to  a  restraint  equal  to  the 
occasion.  Horses  are  very  dissimilar  in  their 
tempers,  and  bear  pain  very  differently  ;  but 
it  is  always  prudent  to  prepare  for  the  worst, 
and  few  important  operations  should  be  at- 
tempted without  casting.  Humanity  should 
be  the  fundamental  principle  of  every  pro- 
ceeding, and  we  ought  always  to  subject 
this  noble  animal  to  pain  with  reluctance ; 
but  when  circumstances  absolutely  call  for 
it,  we  should  joyfully  close  our  hearts  to  aU 
necessary  suffering.  The  resistance  of  the 
horse  is  terrible,  and  it  is  but  common  pru- 
dence to  guard  against  the  effects  of  it.  The 
lesser  restraints  are  various  :  among  them 
may  be  first  noticed  the  tiuitch.  The  twitch 
is  a  very  necessary  instrument  in  a  stable, 
though,  when  frequently  and  officiously 
used,  it  may  have  the  ill  effect  of  rendering 
some  horses  violent  to  resist  its  application. 
In  many  instances  blindfolding  will  do  more 
than  the  twitch ;  and  some  horses  may  be 
quieted,  when  the  pain  is  not  excessive,  by 
holding  the  ear  in  one  hand,  and  rubbing 
the  point  of  the  nose  with  the  other.  A 
soothing  manner  will  often  engage  the  atten- 
tion and  prevent  violence  ;  but  it  is  seldom 
that  either  tlnreats  or  punishment  render  an 
unruly  horse  more  calm.  Inexperienced 
persons  guard  themselves  only  against  the 
hind  legs ;  but  they  should  be  aware  that 
some  horses  strike  terribly  with  their  fore 
*  Blames'  "  Outlines." 


feet:  it  is  prudent,  therefore,  in  all  opera- 
tions, to  blindfold  the  animal,  as  by  this  he 
becomes  particularly  intimidated,  and  if  he 
strikes  he  cannot  aim.  When  one  of  the 
fore  extremities  requires  a  very  minute  ex- 
amination, it  is  prudent  to  have  the  oppo- 
site leg  held  up  ;  it  may,  in  some  cases,  be 
tied :  and  when  one  of  the  hinder  feet  is  the 
object  of  attention,  the  fore  one  of  the  same 
side  should  be  held  up,  as  by  this  means  the 
animal  is  commonly  prevented  from  strik- 
ing. If  this  precaution  be  not  taken,  still 
observe  to  keep  one  hand  on  the  hock,  while 
the  other  is  employed  in  what  is  necessary ; 
by  which  means,  if  the  foot  become  elevated 
to  kick,  sufficient  warning  is  given,  and  the 
very  action  of  the  horse  throws  the  operator 
away  from  the  stroke.  Without  the  use  of 
these  arts  the  practitioner  will  expose  him- 
self to  much  risk.  The  trevis  is  the  very 
utmost  limit  of  restraint,  and  is  seldom  used 
save  by  smiths,  to  shoe  very  violent  and 
powerful  horses :  whenever  recourse  is  had 
to  it,  the  greatest  caution  is  necessary  to 
bed  and  bolster  all  the  parts  that  are  likely 
to  come  in  contact  with  the  body.  On  the 
Continent  we  have  seen  horses  shod  in  this 
machine,  and  apparently  put  into  it  from  no 
necessity  greater  than  to  prevent  the  clothes 
of  the  smith  from  being  dirtied.  Horses 
have  been  destroyed  by  the  trevis,  as  weU 
as  by  casting ;  or  their  aversion  to  the  re- 
straint has  been  such,  they  have  died  from 
the  consequences  of  their  own  resistance. 
The  side-line  is  now  very  generally  used,  not 
only  in  minor  operations,  but  also  in  those 
more  important.  Many  veterinarians  do  not 
use  any  other  restraint  than  this,  in  which 
they  consider  there  is  safety  both  to  the 
horse  and  to  the  operator.  It  is  applicable 
to  such  horses  as  are  disposed  to  strike  be- 
hind ;  and  consists  in  placing  a  hobble  strap 
around  the  pastern  of  one  hind  leg,  and  then 
carrying  from  a  web  collar  passed  over  the 
head  the  end  of  a  rope  through  the  D  of  the 
hobble,  and  back  again  under  the  webbing 
round  the  neck.  A  man  is  then  set  to  pull 
at  the  free  end  of  the  rope,  by  which  the 
hinder  leg  is  drawn  forward  without  elevat- 
ing it  from  the  ground.     By  this  displace- 


260 


A  DICTIONARY. 


ment  of  one  leg  the  horse  is  effectually 
secured  from  lacking  with  cither.  Occasion- 
ally it  is  thus  applied :  hobbles  are  put 
on  both  hind  legs,  and  the  rope  is  passed 
through  eacli  of  the  rings.  According  to 
this  last  method,  the  horse  is  actually  cast, 
as  he  must  fall  when  the  ropes  are  pulled. 
Take  a  long  rope,  and  tie  a  loop  in  the  mid- 
dle, which  is  to  be  of  such  a  size  as  it  may 
serve  for  a  collar ;  pass  the  loop  over  the 
head,  letting  the  knot  rest  upon  the  withers ; 
then  take  the  free  ends,  pass  them  through 
the  hobbles,  and  bring  it  under  the  loop. 
Let  two  men  pull  at  the  ropes,  and  the  hind 
legs  will  be  drawn  forward. 

"  Casting. —  The  objections  to  this  prac- 
tice arise  from  the  dangers  incurred  by  forc- 
ing the  horse  to  the  ground.  IVIr.  Bracy 
Clark  simplified  casting,  by  inventing  some 
patent  hobbles,  having  a  running  chain  in- 
stead of  rope,  and  which,  by  a  shifting  D, 
made  the  loosening  of  all  the  hobbles,  for 
the  purpose  of  getting  at  a  particular  leg, 
unnecessary.  These  were  still  further  im- 
proved by  IVIr.  Budd,  so  as  to  render  a 
release  from  all  the  hobbles  at  once  practi- 
cable. Hobble  leathers  and  ropes  should  be 
kept  supple  and  pliant  with  oil,  and  ought 
to  be  always  examined  previous  to  using  ; 
nor  should  the  D  or  ring  of  the  strap  be  of 
any  other  metal  than  iron.  Brass,  however 
thick,  is  brittle,  and  not  to  be  depended  on. 
To  the  D  or  ring  of  one  pastern  hobble,  a 
chain  of  about  four  feet  long  is  attached ;  to 
this  a  strong  rope  is  well  fastened,  and,  ac- 
cording to  the  way  the  horse  is  to  be  thrown, 
this  hobble  is  to  be  fixed  on  the  fore  foot  of 
the  contrary  side  :  the  rope  is  then  passed 
from  the  hobble  on  the  fore  foot  to  the  D  of 
the  hind  foot  of  that  side,  then  to  the  other 
hind  foot,  and,  lastly,  through  the  D  of  the 
other  fore  foot.  After  this,  much  of  the  ease 
und  safety  of  the  throio  depend  on  bringing 
the  legs  as  near  together  as  possible.  This 
should  be  done  by  gradually  moving  them 
nearer  to  each  other,  without  alarming  the 
horse;  which  will  very  much  facilitate  the 
business,  and  is  really  of  more  moment  than 
is  generally  imagined.  A  space  sufficiently 
large  should  be  chosen  for  the  purpose  of 


casting,  as  some  horses  struggle  much,  and 
throw  themselves  with  great  violence  a  con- 
siderable way  to  one  side  or  the  other  ;  and 
they  are  able  to  do  this  if  the  feet  have  not 
been  brought  7iear  together  previous  to  at- 
tempting the  cast.  The  place  should  be  also 
very  well  littered  down.  The  legs  having 
been  brought  together,  the  assistants  must 
act  in  concert;  one  particularly  should  be 
at  the  head,  which  must  be  carefully  held 
throughout  by  means  of  a  strong  snaffle 
bridle  ;  another  should  be  at  the  hind  part 
to  direct  the  fall,  and  to  force  the  body  of 
the  horse  to  the  side  which  is  requisite. 
Pursuing  these  instructions,  the  animal  may 
be  at  once  rather  let  down  than  thrown,  by 
a  dexterous  and  quick  drawing  of  the  rope  ; 
the  whole  assistants  acting  in  concert.  The 
moment  the  horse  is  down,  the  person  at  the 
head  must  throw  himself  upon  that  mem- 
ber, and  keep  it  secure ;  for  all  the  efforts  of 
the  animal  to  disengage  himself  are  begun 
by  elevating  the  head  and  fore  parts.  The 
rope  is  tightened.  The  chain  is  fixed  by 
inserting  a  hook  through  one  of  the  links, 
of  sufficient  size  not  to  pass  the  hobbles. 
When  the  operation  is  over,  the  screw  which 
fastens  the  chain  to  the  hobble,  first  put  upon 
one  fore  leg,  is  withdrawn.  The  chain  then 
flies  through  the  D's  of  the  other  hobbles, 
and  aU  the  legs  are  free,  save  the  fore  leg 
first  aUuded  to ;  the  strap  of  this  has  to  be 
afterwards  unbuckled.  There  are  also  other 
apparatus  used  in  casting,  as  a  strong 
leathern  case  to  pass  over  the  head,  serving 
as  a  blind  when  the  animal  is  being  thrown ; 
and  as  a  protection  against  his  rubbing  the 
skin  off  his  eyes  when  down.  Then  a  sur- 
cingle is  also  used.  This  is  fastened  round 
the  horse's  body,  and  from  the  back  hangs  a 
broad  strap  and  a  rope :  the  strap  is  fastened 
to  the  fore  leg  of  that  side  which  it  is  de- 
sired should  be  uppermost ;  the  line  is  given 
to  a  man  who  stands  on  the  opposite  side 
to  the  generafity  of  the  puUers.  On  the 
signal  being  given,  the  men  having  hold  of 
the  hobble  rope  puU  the  legs  one  way,  whfle 
he  who  has  hold  of  the  rope  attached  to  the 
surcingle  pulls  the  back  in  a  contrary  direc- 
tion, and  the  horse  is  immediately  cast 


A   DICTIONARY. 


261 


"  Slin^ins:  is  a  restraint  which  horses 
submit  to  with  great  impatience,  and  not 
without  much  inconvenience,  from  the  vio- 
lent excoriations  occasioned  by  the  friction 
and  pressure  of  the  bandaging  around  his 
body.  Graver  evils  are  also  brought  about 
by  the  abdominal  pressure :  some  horses 
stale  and  dung  with  difficulty  when  sus- 
pended ;  and  inflammation  of  the  bowels 
has  not  unfrequently  come  on  during  sling- 
ing. The  slings  are,  however,  forced  on  us 
in  some  cases,  as  in  fractured  bones,  the 
treatment  of  open  joints,  and  some  other 
wounds  where  motion  would  be  most  un- 
favorable to  the  curative  treatment.  Sus- 
pension may  be  partial  or  complete.  Sus- 
pension of  any  kind  wUl  require  the  appli- 
cation of  pulleys  and  ropes  affixed  to  the 
beams,  that  the  whole  body  of  the  horse 
may  be  supported.  A  sling  may  be  formed 
of  a  piece  of  strong  sacking,  which  is  to  pass 
under  the  belly,  the  two  ends  being  fastened 
firmly  to  pieces  of  wood ;  each  of  about 
three  feet  long,  and  which  are  to  reach  a 
little  higher  than  the  horse's  back :  to  the 
pieces  of  wood,  cords  and  pulleys  are  to  be 
firmly  attached,  by  which  means  the  sacking 
can  be  lowered  or  raised  at  pleasure.  To  the 
sacking,  also,  are  to  be  sewn  strong  straps, 
both  before  and  behind,  to  prevent  the  horse 
sliding  in  either  direction,  without  carrying 
the  sacking  with  him.  Upon  this  so-formed 
cradle  he  is  to  recline.  K  horses  when  they 
are  fresh  should  be  placed  in  this  machine, 
most  of  them  would  either  injure  themselves, 
or  break  through  all  restraint.  However,  by 
tying  up  their  heads  for  three  or  four  nights, 
their  spirit  is  destroyed.  The  slings  may 
then  be  applied  without  the  fear  of  resist- 
ance :  it  is  the  best  method  not  to  pull  the 
canvas  firm  up,  but  to  leave  about  an  inch 
between  the  horse's  belly  and  the  cloth,  so 
that  the  animal  may  stand  free,  or  throw  his 
weight  into  the  slings  when  he  pleases.  In 
this  fashion  a  horse  may  remain  for  months 
in  the  slings,  and  at  the  end  of  the  time  dis- 
play none  of  the  wear  and  tear  so  feelingly 
described  by  old  authors. 

."  Castration.  —  This   practice  is  of  very 
ancient  origin ;  and  is  as  extensive  as  ancient. 


It  is  founded  on  the  superior  placidity  of 
temper  it  gives.  The  castrated  horse  no 
longer  evinces  the  superiorities  of  his  mas- 
culine character,  but  approaches  the  softer 
form  and,  milder  character  of  the  mare. 
Losing  his  ungovernable  desires,  he  submits 
to  discipline  and  confinement  without  resist- 
ance ;  and,  if  he  be  less  worthy  of  the  paint- 
er's defineation  and  the  poet's  song,  he  is 
valuable  to  his  possessor  in  a  tenfold  degree. 
In  England,  where  length  in  the  arms  and 
of  the  wide  spread  angles  of  the  limbs  is  ab- 
solutely necessary  in  the  horse  to  accomplish 
the  rapid  travelling  so  much  in  vogue  among 
us,  the  exchange  of  the  lofty  carriage  and 
high  action  of  the  stallion  is  absolutely 
necessary ;  and,  when  we  have  added  the 
lessened  tendency  of  the  gelding  to  some 
diseases,  as  hernia,  founder,  cutaneous 
affections,  etc.,  we  may  be  content  to  leave 
the  sexual  type  with  the  racer  for  his  breed ; 
also  with  the  drayhorse  for  his  weight,  and 
the  fancy  of  his  owner.  Supposing  it, 
therefore,  eligible  to  castrate  our  horses, 
what  is  the  proper  age  for  the  operation  ? 
What  are  the  relative  advantages  and  dis- 
advantages of  the  different  methods  of  per- 
forming it  ?  The  proper  age  to  castrate 
the  young  horse  must  depend  on  circum- 
stances ;  as  on  his  present  appearance,  his 
growth,  and  the  future  purposes  we  intend 
him  for ;  observing,  generally,  that  the  more 
early  it  is  done,  the  safer  is  the  operation : 
for,  until  these  organs  begin  to  secrete,  they 
are  purely  structural  parts,  and  as  such  are 
not  so  intimately  connected  with  the  sym- 
pathies of  the  constitution.  Some  breeders 
of  horses  castrate  at  twelve  months  ;  others 
object  to  this  period,  because  they  think  the 
animal  has  not  sufficiently  recovered  the 
check  experienced  from  weaning,  before  this 
new  shock  to  the  system  occurs.  In  the  more 
common  sort  of  horses  used  for  agricultural 
purposes,  it  is  probably  indifferent  at  what 
time  the  operation  is  performed ;  this  con- 
sideration being  kept  in  view,  that  the 
earlier  it  is  done  the  lighter  wUl  the  horse 
be  in  his  fore-hand;  and  the  longer  it  is 
protracted  the  heavier  will  be  his  crest,  and 
the   greater   his  weight   before,   which   in 


262 


A   DICTIONARY. 


heavy  draught  work  is  desirable.  For  car- 
riage horses  it  would  be  less  so,  and  the 
period  of  two  years  is  not  a  bad  one  for 
their  casti-ation.  The  better  sort  of  saddle- 
horses  should  be  well  examined  every  three 
or  four  months  ;  particularly  at  the  ages  of 
twelve,  eighteen,  and  twenty-four  months  ; 
at  either  of  which  times,  according  to  cir- 
cumstances or  to  fancy,  provided  the  fore- 
hand be  sufficiently  developed,  it  may  be 
proceeded  with.  Waiting  longer  may 
make  the  horse  heavy ;  but,  if  his  neck  ap- 
pear too  long  and  thin,  and  his  shoulders 
spare,  he  will  assuredly  be  improved  by  be- 
ing allowed  to  remain  entire  for  six  or  eight 
months  later.  Many  of  the  Yorkshu-e 
breeders  never  cut  till  two  years,  and  think 
theh'  horses  stronger  and  handsomer  for  it : 
some  wait  even  longer,  but  the  fear  in  this 
case  is,  that  the  stallion  form  wiU  be  too 
predominant,  and  a  heavy  crest  and  weighty 
fore-hand  be  the  consequence ;  perhaps  also 
the  temper  may  suffer.  Young  colts  requne 
little  preparation,  provided  they  are  healthy 
and  not  too  full  from  high  living ;  if  so, 
they  must  be  kept  somewhat  short  for  a  few 
days  ;  and  in  all,  the  choice  of  a  mild  season 
and  moderate  temperature  is  proper.  When 
a  full  grown  horse  is  operated  on,  some  fur- 
ther preparation  is  necessary.  He  should 
not  be  in  a  state  of  debility,  and  certainly 
not  in  one  of  plethora :  in  the  latter  case, 
lower  his  diet,  and  it  would  be  prudent  to 
give  him  a  purgative.  It  is  also  advisable 
that  it  be  done  when  no  influenza  or  stran- 
gles rage,  as  we  have  found  the  effects  of 
castration  render  a  horse  very  obnoxious  to 
any  prevalent  disease.  The  advanced  spring 
season,  previous  however  to  the  flies  becom- 
ing troublesome,  is  the  proper  time  for  the 
performance  of  the  operation  upon  all  valu- 
able horses ;  and  be  careful  that  it  be  not 
done  until  after  the  winter  coat  has  been 
shed,  which  will  have  a  favorable  effect  on 
the  future  coating  of  the  horse,  independent 
of  the  circumstance,  that  at  a  period  of 
change  the  constitution  is  not  favorable  to 
any  unusual  excitement. 

"  Castration  is  performed  in  various  ways, 
but  in  all  it  expresses  the  removal  of  the 


testicles;  there  are  methods  of  rendering 
the  animal  impotent  without  the  actual  de- 
struction of  these  organs ;  for  if  by  any 
other  method  the  secretion  of  the  spermatic 
glands  is  prevented,  our  end  is  answered. 

"  Castration  by  cauterization  is  the  method 
which  has  been  principally  practised  among 
us.  But  this  by  no  means  proves  it  the  best; 
on  the  contrary,  many  of  our  most  expert 
veterinarians  do  not  castrate  by  this  method. 
Ml-.  Goodwin,  and  many  other  practitioners 
of  eminence,  never  castrate  by  cautery. 

"  A  preliminary  observation  should  be 
made  previously  to  casting,  to  see  that  the 
horse  is  not  suffering  from  a  rupture :  such 
cases  have  happened  ;  and  as  in  our  method 
we  open  a  direct  communication  with  the 
abdomen,  when  the  horse  rises  it  is  not  im- 
probable that  his  bowels  protrude  until  they 
trail  on  the  ground.  Hernia  as  a  conse- 
quence of  castration  may  easily  occur  by 
the  uncovered  operation ;  for,  as  already 
observed,  it  makes  the  scrotal  sac  and  ab- 
dominal cavity  one  continuous  opening. 
It  is  not  to  be  wondered  at,  therefore,  if  the 
violent  struggles  of  the  animal  should  force 
a  quantity  of  intestine  through  the  rings 
into  the  scrotal  bag.  Should  we  be  called 
on  to  operate  on  a  horse  which  already  had 
hernia,  it  is  evident  we  ought  not  to  proceed 
with  it,  unless  the  owner  be  apprised  of  the 
risk,  and  willing  to  abide  by  it.  In  such 
case  we  would  recommend  that  the  method 
of  Girard  be  practised,  i.  e.  to  inclose  the 
tunica  vaginalis  within  the  clams  (suffi- 
ciently tight  to  retain  them,  but  not  to  pro- 
duce death  in  the  part)  pushed  high  up 
against  the  abdominal  ring,  and  then  to  re- 
move the  testicle,  being  very  careful  to 
avoid  injuring  any  portion  of  intestine  in 
the  operation.  When  a  discovery  is  made 
of  the  existence  of  hernia  after  an  opening 
has  been  already  made  for  the  common  pur- 
pose of  castration,  should  the  operator  con- 
tinue his  process,  and  castrate  ?  We  should 
say,  by  no  means ;  but,  on  the  contrary,  we 
would  greatly  prefer  the  method  recom- 
mended by  ]\'Ir.  PervicaU, — firmly  to  unite 
the  lips  of  the  external  wound  by  suture, 
allowing  the  testicle  itself  to  assist  in  block- 


A   DICTIONARY. 


263 


ing  up  the  passage ;  with  a  hope  also  that 
the  inflammation  caused  by  the  excision 
might  altogether  stop  up  the  scrotal  com- 
munication with  the  abdomen.  But,  in  the 
appalling  case  of  immense  protrusion  of 
intestine,  what  is  to  be  done  ?  Mr.  Cole- 
man, in  such  a  case,  proposes  to  make  an 
opening  near  the  umbilicus,  large  enough 
to  introduce  the  hand,  and  thus  draw  in  the 
bowels.  Mr.  Percivall  would  prefer  dilating 
the  external  ring :  but  the  testicle  must  be 
very  firmly  retained,  and  even  permanently 
fixed  against  the  dilated  ring,  or  the  bowels 
would  again  descend.  The  intestines 
probably  would  become  inflated  in  any 
such  case. 

"  As  unbroken  young  horses  are  the  most 
usual  subjects  of  this  operation,  and  as  such 
often  have  not  yet  been  bridled,  if  a  colt 
cannot  be  enticed  with  oats,  etc.,  he  must 
be  driven  into  a  corner  between  two  steady 
horses ;  where,  if  a  halter  cannot  be  put  on, 
at  least  a  running  hempen  noose  can  be  got 
round  his  neck  ;  but,  which  ever  is  used,  it 
should  be  flat,  or  the  struggles,  which  are 
often  long  and  violent,  may  bruise  the  neck, 
and  produce  abscess  or  injury.  When  his 
exertions  have  tired  him,  he  may  be  then 
led  to  the  operating  spot ;  here  his  attention 
should  be  engaged  while  the  hobbles  are 
put  on,  if  possible ;  if  not,  a  long  and  strong 
cart-rope,  having  its  middle  portion  formed 
into  a  noose  sufficiently  large  to  take  in  the 
head  and  neck,  is  to  be  slipped  on,  with  the 
knotted  part  applied  to  the  counter  or  breast ; 
the  long  pendant  ends  are  passed  back- 
ward between  the  fore  legs,  then  carried 
round  the  hind  fetlocks ;  brought  forward 
again  on  the  outside,  run  under  the  collar- 
rope  ;  a  second  time  carried  backward  on 
the  outer  side  of  all,  and  extended  to  the 
full  length  in  a  direct  line  behind  the  animal. 
Thus  fettered,  Mr.  Percivall  says  his  hind 
feet  may  be  drawn  under  him  toward  the 
elbows ;  it  has  been,  however,  often  found 
that,  at  the  moment  the  rope  touches  the 
legs,  the  colt  either  kicks  and  displaces  the 
rope,  or  altogether  displaces  himself;  but 
his  attention  can  generally  be  engaged  by 
one  fore  leg  being  held  up,  or  by  having  his 


ear  or  muzzle  rubbed,  or  even  by  the  twitch ; 
if  not,  the  rope  may  be  carried  actually 
round  each  fetlock,  which  then  acts  like  a 
hobble;  and  this  rope  may  be  gradually 
tightened :  this  last,  however,  is  a  very  ques- 
tionable method,  and  the  others  therefore 
ought  to  be  long  tried  before  it  is  resorted 
to ;  in  this  way  people  have  succeeded  with 
very  refractory  colts ;  but  it  requires  very 
able  assistants,  and,  if  possible,  the  man 
who  has  been  used  to  the  individual  colt 
should  be  present.  In  either  way,  as  soon 
as  the  rope  is  fixed,  with  a  man  to  each  end 
of  it  behind  the  colt,  let  them,  by  a  sudden 
and  forcible  effort  in  concert,  approximate 
his  hind  legs  to  his  fore,  and  thus  throw 
him.  Before  the  colt  is  cast,  however,  it 
should  be  endeavored  to  ascertain  that  he 
is  free  from  strangles  and  hernia. 

"  Being  satisfied  that  no  hernia  exists  on 
either  side,  proceed  to  cast  the  colt,  tm*ning 
him,  not  directly  on  the  left  side,  but  prin- 
cipally inclining  that  way ;  and,  if  possible, 
let  the  croup  be  very  slightly  elevated  ;  it  is 
usual  to  place  him  directly  flat  on  the  left 
side,  but  the  above  is  more  convenient. 
Next  secm'e  the  near  hind  leg  with  a  piece 
of  hempen  tackle,  having  a  running  noose  ; 
or,  in  default  of  this  not  being  at  hand, 
make  use  of  the  flat  part  of  a  hempen  hal- 
ter, which  should  for  safety  be  put  on  be- 
fore the  hobble  of  that  leg  is  removed ;  as 
may  be  readily  done,  if  the  hobbles  having 
shifting  or  screw  D's,  as  described  in  cast- 
ing, are  made  use  of.  Every  requisite  being 
at  hand,  the  operator,  having  his  scalpel 
ready,  should  place  himself  behind  the 
horse,  as  the  most  convenient  way  to  per- 
form his  manipulations ;  and,  firmly  grasp- 
ing the  left  testicle  with  his  left  hand,  and 
drawing  it  out  so  as  to  render  the  scrotum 
tense,  he  should  make  an  incision  length- 
ways, from  the  anterior  to  the  posterior 
part  of  the  bag.  The  resistance  of  the 
cremaster  muscle  has  to  be  overcome  be- 
fore the  testicle  can  be  forced  to  the  bottom 
of  the  scrotum ;  and  this  is  the  more  readily 
accomplished  if  the  annimal's  attention  be 
engaged.  The  incision  may  be  carried  at 
once  through  the  integuments,  the  thin  dar- 


264 


A   DICTIONARY. 


tos  expansion,  and  the  vaginal  coat  of  the 
testicles,  with  a  sweep  of  the  scalpel :  but 
with  one  less  dexterous  at  the  operation,  it 
will  be  more  prudent  to  make  the  first  in- 
cision through  the  scrotum  and  dartus  only, 
to  the  required  extent ;  and  then  to  do  the 
same  by  the  vaginal  coat,  thus  avoiding  to 
wound  the  testicle,  which  would  produce 
violent    resistance,  and    give   unnecessary 
pain.     We,  however,  take  this  opportunity 
of  noting,  that  cases  have  occurred,  when 
the  tunica  vaginalis  was  divided,  no  testicle 
followed ;  firm  adhesions  between  this  tunic 
and  the  tunica  albuginea  having  retained  it 
fast.     In  such  cases  the  scalpel  must  be 
employed  to  free  the  testicle,  by  dissecting 
it  away  from  the  vaginal  sac.     When  no 
such  obstruction  occurs,  the  testicle,  if  the 
opening  be  sufficiently  large,  will  slip  out ; 
but  the  operator  must  be  prepared  at  the 
moment  of  so  doing  to  expect  some  violent 
struggles,  more  particularly  if  he  attempt 
to  restrain  the  contractions  of  the  cremas- 
ter,  and  by  main  force  to  draw  out  the  tes- 
ticle.    Preparatory   to   this,    therefore,   the 
twitch  should  be  tightened ;  the  attendants, 
especially  the  man  at  the  head,  must  be  on 
the  alert ;  and  the  testicle  itself,  at  the  time 
of  this  violent  retraction  of  the  cremaster, 
should  be  merely  held,  but  not  dragged  in 
opposition  to  the  contraction.     If  the  clams 
have  been  put  on  over  the  whole,  according 
to  Mr.  Percivall's   method,  they  will  assist 
in  retaining  the  retracting  parts ;  but  they 
must  not  be  used  with  too  much  pressure. 
The  resistance  having  subsided,  the  clams 
must  now  be  removed  ;  or,  if  they  have 
not  been  previously  in  use,  they  must  now 
be  taken  in  hand,  and,  having  been  prepared 
by  some   tow  being  wound  round   them, 
should  be  placed  easily  on  the  cord,  while 
time  is  found  to  free  from  the  grip  of  the 
pincers  the  vas  deferen^^  or  spermatic  tube, 
which  is  seen  continued  from  the  epididy- 
mis.    The  Russians,  Mr.  Goodwin  informs 
us,  cut  it  through  when  they  operate.     Hu- 
manity is  much   concerned  in  its  removal 
from    pressure,  because    of   the    excess  of 
pain  felt  when  it  is  included.     It  is  neces- 
sary, before  the  final  fixing  of  the  clams,  to 


determine  on  the  part  where  the  division  of 
the  cord  is  to  talce  place.  To  use  Mr.  Per- 
civall's words,  '  K  it  be  left  too  long,  it  is 
apt  to  hang  out  of  the  wound  afterward, 
and  retard  the  process  of  union;'  on  the 
other  hand,  if  it  be  cut  very  short,  and  the 
arteries  happen  to  bleed  afresh  after  it  has 
been  released  from  the  clams,  the  operator 
will  find  it  no  easy  task  to  recover  it.  The 
natural  length  of  the  cord,  which  will  mainly 
depend  on  the  degree  of  the  descent  of  the 
gland,  will  be  our  best  guide  in  this  partic- 
ular. The  place  of  section  determined  on  and 
marked,  close  the  clams  sufficiently  tight  to 
retain  firm  hold  of  the  cord,  and  to  effectu- 
ally stop  the  circulation  within  it.  There 
are  now  two  modes  of  making  the  division : 
the  one  is  to  sever  it  with  a  scalpel,  and 
then  to  sufficiently  sear  the  end  of  it  as  to 
prevent  a  flow  of  blood.  The  other,  and 
in  some  respects  the  preferable  method,  is 
to  employ  a  blunt-edged  iron,  which  is  to 
divide  by  little  crucial  sawings,  so  that, 
when  the  cord  is  separated,  it  shall  not  pre- 
sent a  uniform  surface,  but  ragged  edges, 
which  will  perfectly  close  the  mouths  of  the 
vessels.  This  done,  loosen  the  clams  suf- 
ficiently to  observe  whether  there  be  any 
flow  of  blood  ;  gently  wipe  the  end  of  the 
cord  also  with  the  finger,  as  sometimes  an 
accidental  small  plug  gets  within  the  vessel; 
this  had  better  be  removed  at  the  time. 
Retain  a  hold  on  the  clams  a  few  minutes 
longer ;  and,  while  loosening  them  gradu- 
ally, observe  to  have  an  iron  in  readiness 
again  to  touch  the  end  of  the  cord,  if  any 
blood  makes  its  appearance.  Satisfied  on 
this  point,  sponge  the  parts  with  cold  water ; 
no  sort  of  external  application  is  necessary, 
still  less  any  resin  seared  on  the  end  of  the 
cord,  which  can  only  irritate,  and  will  never 
adhere.  On  the  after-treatment  much  dif- 
ference of  opinion  has  existed,  and  even  yet 
exists.  The  powerful  evidence  of  accumu- 
lated facts  has  now  convinced  us  of  the 
necessity  and  propriety  of  some  motion  for 
the  newly  castrated  horse,  as  a  preventive 
of  local  congestion ;  such  practice  is  com- 
mon in  most  countries,  and  seems  salutary 
in  all.     Hurtrel  d'Ai'boval,  thus  impressed, 


A   DICTIONARY. 


265 


recommends  the  horse,  immediately  after 
the  operation,  to  be  led  out  to  walk  for  an 
horn' ;  and  it  is  a  general  plan  in  France  to 
walk  such  horses  in  hand  an  hour  night  and 
morning.  Mr.  Goodwin,  in  proof  of  its 
not  being  hurtful,  informs  us  that  whole 
studs  of  horses,  brought  to  St.  Petersburgh 
to  be  operated  on,  are  immediately  travelled 
back  a  certain  portion  of  the  distance,  night 
and  morning,  until  they  arrive  at  home. 
We  have,  therefore,  no  hesitation  in  recom- 
mending a  moderate  degree  of  motion  in 
preference  to  absolute  rest. 

"  The  French  method  of  castration  is  advo- 
cated by  Ml".  Goodwin  ;  and  it  is  sufficient 
that  it  receives  his  recommendation  to  en- 
title it  to  attention  ;  it  is  rendered  the  more 
so,  as  he  observes  on  the  method  in  general 
use  among  us,  '  that  the  operation  per- 
formed by  the  actual  cautery  always  in- 
duces, more  or  less,  symptoms  that  often 
become  alarming;  and  that  it  cannot  be 
performed  on  the  adult  without  incurring 
more  swelling  and  severer  consequences 
than  attend  other  methods  of  operation.  If 
I.  ever  use  the  actual  cautery,  it  is  for  the 
sake  of  expedition,  and  then  only  on  a 
yearling,  or  a  two-year  old ;  but  I  am  re- 
solved never  to  employ  it  again  on  an 
adult.'  These  observations,  as  emanating 
from  such  a  source,  must  be  deemed  im- 
portant. Mr.  Goodwin  then  offers  the  de- 
scription of  the  French  method  of  operating, 
from  Hurtrel  d'Arboval.  '  Castration,  by 
means  of  the  clams,  is  the  method  in  gen- 
eral use,  if  not  the  only  one  now  employed ; 
it  is  the  most  ancient,  since  it  was  recom- 
mended by  Hieroclius  among  the  Greeks. 
It  is  performed  in  two  ways,  the  testicle 
being  covered  or  uncovered.  In  the  former, 
the  exterior  of  the  scrotum,  formed  by  the 
skin  and  dartos  muscle,  is  cut  through,  and 
the  testicle  is  brought  out  by  dissecting 
away  the  laminated  tissue,  the  gland  being 
covered  by  the  tunica  vaginalis  ;  the  clam 
is  then  placed  above  the  epididymis,  outside 
the  external  peritoneal  covering,  of  the  cord. 
In  the  uncovered  operation,  the  incision  is 
made  through  the  servus  capsule  of  the  tes- 
ticle ;  the  tunica  vaginalis   being  divided, 

34 


the  testicle  presents  itself,  and  the  clam  is 
placed  well  above  the  epididymis,  on  the 
cord.  The  operation,  performed  in  either 
way,  requires  us  to  provide  ourselves  with  a 
scalpel,  a  pair  of  clams,  a  pair  of  long  pin- 
cers, made  purposely  to  bring  the  ends  of 
the  clams  together,  and  some  waxed  string. 
The  clams  may  be  formed  of  different  kinds 
of  wood ;  but  the  elder  is  considered  the 
best,  and  generally  made  use  of.  To  make 
a  clam,  we  procure  a  branch  of  old  and  dry 
elder,  whose  diameter  should  be  about  an 
inch,  and  whose  length  should  be  from  five 
to  six  inches  :  of  course,  the  dimensions 
must  at  all  times  be  proportioned  to  the 
size  of  the  cord  we  have  to  operate  on.  At 
the  distance  of  half  an  inch  from  each  end, 
a  small  niche,  sufficiently  deep  to  hold  the 
string,  must  be  made,  and  then  the  wood 
should  be  sawed  through  the  middle  length- 
ways. Each  divided  surface  should  be 
planed,  so  as  to  facilitate  the  opening  of 
the  clams,  either  when  about  to  place  them 
on  or  take  them  off.  The  pith  of  the  wood 
is  then  to  be  taken  out,  and  the  hollow 
should  be  filled  with  corrosive  sublimate  and 
flour,  mixed  with  sufficient  water  to  form  it 
into  a  paste.  Some  persons  are  not  in  the 
habit  of  using  any  caustic  whatever ;  then, 
of  course,  scooping  out  of  the  inside  of  the 
clam  is  not  necessary :  notwithstanding,  the 
caustic,  inasmuch  as  it  produces  a  speedier 
dissolution  of  the  parts,  must  be  useful,  and 
ought  not  to  be  neglected.'  The  addition 
of  the  caustic,  however,  Mr.  Goodwin  ob- 
jects to  with  great  reason,  remarking,  that 
unless  it  be  a  very  strong  one,  and  therefore 
dangerous  to  employ,  it  cannot  be  of  any 
use  to  parts  compressed  and  deprived  of 
cuculation  and  life.  He  further  informs  us 
that  he  has  operated  in  six  cases  in  succes- 
sion with  the  same  effect,  without  any  es- 
charotic  matter  whatever.  An  experimental 
case  of  Mr.  Percivall's  terminated  fatally: 
by  the  use  of  caustic  the  cord  was  greatly 
inflamed,  as  high  as  the  ring,  and  which 
unquestionably  produced  the  unfortunate 
result.  '  The  covered  operation,'  continues 
Mr.  Goodwin,  '  is  the  one  that  I  am  about 
to  advocate,  and  which  differs  only  inso- 


266 


A   DICTIONARY. 


much,  that  the  scrotum  and  dartos  muscle 
must  be  cautiously  cut  through,  without 
dividing  the  tunica  vaginalis.  It  was  Mon- 
sieur Berger,  who  was  accidentally  at  my 
house  when  I  was  about  to  castrate  a  horse, 
and  who,  on  my  saying  that  I  should  prob- 
ably do  it  with  the  cautery,  expressed  his 
surprise  that  I  should  perform  the  operation 
in  any  other  way  than  on  the  plan  generally 
approved  of  in  France.  Being  a  stranger 
to  it,  he  Idndly  consented  to  preside  at  the 
operation,  and,  after  seeing  him  perform  on 
the  near  testicle,  I  did  the  same  on  the 
right,  but,  of  com-se,  not  with  the  same  fa- 
cility. After  opening  the  scrotum,  and 
dissecting  tlnrougii  the  dartos,  which  is  very 
readily  done  by  passing  the  knife  lightly 
over  its  fibres  ;  the  testicle,  and  its  covering, 
the  tunica  vaginalis,  must  be  taken  in  the 
right  hand,  while  the  left  should  be  em- 
ployed in  pushing  back  the  scrotum  from 
its  attachments ;  and,  having  your  assistant 
ready,  as  before,  with  the  clam,  it  must  be 
placed  well  above  the  epididymis,  and  great- 
er pressure  is,  of  course,  necessary,  as  the 
vaginal  covering  is  included  in  the  clam.' 

"  Mr.  Goodwin  further  observes,  that  in 
Russia  he  has  seen  hundreds  of  horses  op- 
erated on,  even  after  the  human  fashion, 
with  safety ;  and,  he  remarks,  it  certainly 
produces  less  pain,  the  animal  loses  less 
flesh  and  condition,  and  is  sooner  recovered 
than  when  operated  on  by  the  actual  cautery. 

"  Castration  by  ligature  is  a  painful,  bar- 
barous, and  very  dangerous  practice  :  and 
consists  in  inclosing  the  testicles  and  scro- 
tum within  ligatures,  until  mortification  oc- 
curs, and  they  drop  off".  It  is  practised  by 
some  breeders  on  their  young  colts,  but  it 
is  always  hazardous,  and  disgracefully  cruel. 
The  substance  of  the  testicle  in  some  coun- 
tries is  also  broken  down  either  by  rubbing, 
or  otherwise  by  pressure  between  two  hard 
bodies  :  this  is  practised  in  Algiers,  instead 
of  excision,  and  tetanus  is  a  frequent  con- 
sequence of  it.  In  Portugal  they  twist 
round  the  testicle,  and  thus  stop  the  circu- 
lation of  the  gland.  Division  of  the  vas 
deferens  has  been  performed,  it  is  said,  with 
success,  on  many  animals  ;  and  is  proposed 


as  a  safe  and  less  painful  process  than  the 
emasculation  of  the  horse.  It  consists  in  a 
longitudinal  section  through  the  scrotum, 
dartos,  and  vaginal  sheath,  so  as  to  expose 
the  cord,  from  which  the  vas  deferens  is  to 
be  separated  and  severed  from  the  artery  and 
vein.  There  is  a  certain  consent  of  parts, 
by  which  the  sympathy  of  an  organ  remains 
after  its  functional  offices  are  apparently 
destroyed.  There  can  be  little  doubt  but 
the  nervous  excitement  would  continue,  the 
vein  and  artery  remaining  entire.  There 
are  certain  nice  conditions  of  the  organ 
necessary  for  propagatioft ;  thus,  the  horse 
who  retains  his  testicles  within  his  abdo- 
men, possesses  all  the  roguish  qualities  of 
him  with  one  perfectly  evolved  :  he  is  lust- 
ful, and  can  cover,  but  is  seldom  fruitful. 
Of  the  morbid  consequences  of  castration 
we  have  little  to  say  :  by  early  evacuations, 
green  food,  a  loose  box,  a  cool  air,  moderate 
clothing,  but  particularly  by  walking  exer- 
cise, swellings  of  the  parts  may  be  prevent- 
ed :  if  not,  bleed  and  foment ;  should  sup- 
puration follow,  and  sinuses  form,  treat  as 
directed  under  those  heads ;  and  if  tetanic 
symptoms  start  up,  refer  to  that  article. 
There  has  been  lately  practised  in  India  a 
novel  mode  of  castration,  which  is  said  to  be 
the  invention  of  a  Boer  settled  at  the  Cape 
of  Good  Hope.  The  cord  is  exposed  in  the 
usual  manner  ;  from  the  cord  the  artery  is 
singled  out ;  this  vessel  is  scraped  through 
with  a  coarse-edged  blunt  knife,  when  the 
other  constitutents  of  the  cord  are  cut  away, 
and  the  operation  is  finished.  This  method 
is  much  praised  by  those  who  have  adopted 
it,  and  is  said  to  be  always  attended  with 
success. 

^'■Lithotomy.  —  Hurtrel  d'Arboval's  ac- 
count of  the  progress  of  lithotomy  in  veteri- 
nary practice  commences  in  1774.  The 
second  case  was  successfully  operated  on  in 
1794  ;  and  at  later  periods  other  veterinary 
surgeons  have  also  performed  it.  '  In  mo- 
nodactyles  there  are  two  methods  of  oper- 
ating for  the  stone  ;  one  through  the  rectum, 
the  other  through  the  bladder.  The  first, 
which  consists  in  lying  open  the  bladder  by 
a  longtitudinal  incision  made  through  the 


A  DICTIONARY. 


267 


parietes  of  the  part  of  the  rectum  adherent 
to  it,  by  means  of  a  straight  bistoury,  is 
easily  practised  ;  but  in  its  consequences  is 
dangerous  in  the  extreme :  in  fact,  it  is  an 
operation  never  to  be  adopted  but  in  a  case 
where  the  magnitude  of  the  stone  precludes 
its  extraction  through  the  neck  of  the  blad- 
der. In  all  other  cases,  lithotomy  by  the 
urethra  is  to  be  pursued.  For  its  perfor- 
mance, are  required  a  straight  probe-pointed 
bistoury,  a  whalebone  fluted  staff,  and  a 
pair  of  forceps  curved  at  the  extremities. 
The  animal  should,  if  practicable,  be  main- 
tained in  the  erect  posture.  The  tail  plaited 
and  carried  round  on  the  right  quarter,  the 
operator  feels  for  the  end  of  the  staff  intro- 
duced up  the  urethra,  and  makes  an  incision 
directly  upon  it,  from  above  downwards,  an 
inch  and  a  half  or  two  inches  in  length. 
Next,  he  introduces  the  sound,  and  passes 
it  onward  into  the  bladder.  Now,  placing 
the  back  of  the  bistoury  within  the  groove 
of  the  sound,  by  gliding  the  knife  forwards, 
the  pelvic  portion  of  the  urethra,  and  also 
the  neck  of  the  bladder,  become  slit  open ; 
the  latter  in  two  places,  in  consequence  of 
a  second  cut  being  made  in  withdrawing 
the  bistoury.  The  opening  made  being 
considered  of  sufficient  dimensions,  the  oper- 
ator introduces  the  forceps  into  the  bladder, 
and  seizes  the  calculus,  one  hand  being  up 
the  rectum,  to  aid  him  in  so  doing.  The 
forceps  clasping  the  stone  are  now  to  be 
withdrawn,  but  with  gentleness ;  and  with  a 
vacillating  sort  of  movement  of  the  hand 
from  side  to  side,  in  order  more  easily  to 
surmount  any  difficulties  in  the  passage,  and 
the  more  effectually  to  avoid  contusion  or 
laceration.  M.  Girard  tells  us,  '  That  the  cut 
through  the  pelvic  portion  of  the  urethra 
ought  always  to  be  made  obliquely  to  one 
side  ;  the  operator  should  hold  his  bistoury 
in  such  a  direction  that  its  cutting  edge  be 
turned  toward  the  angle  of  the  thigh.  By 
this  procedure  we  shall  gain  easier  access  to 
the  bladder  ;  and  not  only  avoid  wounding 
the  rectum,  but  also  the  artery  of  the  bulb, 
as  well  as  the  bulb  itself,  and  suspensory 
ligaments  of  the  penis.'  The  parts  cut 
through  in  the  operation  are,  1st,  the  fine 


thin  skin  of  the  perineum,  smooth  externally 
and  marked  with  a  raphe ;  densely  cellular 
internally  :  2ndly,  adhering  to  the  tissue, 
the  faschial  coverings  derived  from  the  fas- 
chia  superficialis  abdominis,  which  has  here 
become  fibrous :  it  forms  the  common  en- 
velope to  the  parts  underneath,  and  is  closely 
connected  with  the  corpus  musculosum  ure- 
thrse  :  Srdly,  the  corpus  musculosum  urethrcB, 
that  penniform  band  of  fleshy  fibres  wliich 
springs  by  two  branches  from  the  ischiatic 
tuberosities  embracing  the  sphincter  ani,  and 
concealing  the  arteries  of  the  bulb ;  whence 
they  unite,  and  proceed  to  envelop  the 
urethra:  4thly,  the  corpus  spongiosum  ure- 
thr(B,  the  part  immediately  covered  by  the 
muscular  envelope,  and  which  here  is  bulb- 
ous. It  is  more  particularly  worthy  our 
remark,  from  two  arteries  penetrating  the 
bulb,  which  come  from  without  the  pelvis, 
ascending  obliquely  outward  to  reach  the 
part :  5thly,  the  suspensory  ligaments  of  the 
penis,  pursuing  the  course  of,  and  adhering 
to,  the  tendinous  union  of  the  erectores. 
An  attention  to  the  relative  position  of  these 
parts  will  demonstrate  the  advantages  of 
the  lateral  oblique  incision  over  one  made 
directly  along  the  raphe :  by  pursuing  the 
latter,  we  necessarily  cut  through  the  sus- 
pensory ligaments  and  into  the  bulb,  wound- 
ing thereby  the  arteries;  whereas,  by  the 
former,  all  this  danger  is  avoided,  besides 
that  it  renders  the  operation  more  simple 
and  facile. 

"  Tracheotomy.  —  Cases  occur  when  this 
operation  is  required ;  as  in  strangles,  when 
the  tumors  threaten  suffocation,  or  when 
any  substance  has  remained  unswallowed 
in  the  oesophagus,  the  pressure  of  which  ob- 
structs respiration.  In  a  distressing  case  of 
gunpowder  bursting  immediately  under  a 
horse's  nose,  the  effects  of  which  tumefied 
his  mouth  and  nostrils,  so  as  to  prevent  free 
inspiration,  the  animal  owed  his  life  en- 
tirely to  our  excising  a  portion  from  the 
tracheal  rings,  about  ten  inches  below  the 
angle  of  the  throat.  The  operation  is  a  very 
simple  one,  and  may  consist  either  in  a 
longtitudinal  section  made  through  two  or 
three  of  the  rings,  or  a  portion,  occupying 


268 


A  DICTIONARY. 


about  an  inch  round,  may  be  excised  from 
the  anterior  cartilaginous  substance.  The 
proper  mode,  when  it  can  be  done,  however, 
is  to  make  a  circular  opening  with  a  very- 
narrow  knife,  removing  a  portion  of  two 
cartilages,  or  taking  a  semicircular  piece  from 
each ;  and  this  last,  although  it  is  seldom 
performed,  is  by  far  the  best  method :  the 
integuments  should  be  first  divided  in  the 
exact  centre  of  the  neck,  three  or  four  inches 
below  the  obstruction;  then  the  skin  and 
tissues  should  be  sufficiently  separated  to 
allow  a  tube  adapted  to  the  size  of  the  tra- 
chea to  be  introduced ;  the  tube  having  an 
acute  turn  and  a  rim,  which  must  be  fur- 
nished with  holes  for  the  adaptation  of  tapes 
to  secure  it  around  the  neck.  There  are 
several  instruments  of  this  sort  in  use,  of 
which  that  adopted  by  the  French,  or  the 
one  invented  by  ]\Ir.  Gowing  of  Camden- 
Town,  is  to  be  preferred.  The  operation 
has  been  also  performed  in  cases  of  roaring, 
under  an  idea  of  dividing  the  stricture  which 
impeded  respiration ;  but,  unless  the  exact 
situation  of  this  were  discovered,  it  would 
be  but  an  experimental  attempt. 

"  GEsophagotomy.  —  It  was  long  thought 
that  a  wound  in  the  cEsophagus  must  be 
necessarily  fatal,  but  we  have  now  sufficient 
proofs  to  the  contrary  on  record;  so  that 
we  are  not  deterred  from  cutting  into  the 
esophageal  tube  when  it  is  necessary ;  but 
it  is  "an  operation  requiring  skUl  and  anato- 
mical knowledge ;  and  its  future  results  are 
sometimes  very  serious.  The  cases  that 
call  for  esophagotomy  are  the  lodgment  of 
accidental  substances  within  the  tube.  An 
apple  once  so  lodged  was  removed  by  inci- 
sion by  a  veterinary  surgeon  at  Windsor. 
Carrots,  parsneps,  beets,  etc.,  are  liable  to 
produce  such  obstruction  when  not  sliced. 
Too  large  a  medicinal  mass  also  has  lodged 
there ;  and  a  voracious  eater  has,  by  at- 
tempting to  swallow  too  large  a  quantity  of 
not  salivated  bran  or  chaff,  produced  an  ob- 
struction which  pressed  on  the  trachea  and 
tlu-eatcncd  suffocation.  In  all  cases  of  ob- 
struction of  this  kind  we  will  suppose  that  a 
probang  well  oiled  has  been  previously  at- 
tempted to  be  passed,  and  has  completely 


failed.  The  probang  for  the  horse,  however, 
differs  materially  from  that  used  for  the  cow. 
It  is  formed  after  the  fashion  of  the  one 
adopted  by  the  human  practitioner,  consist- 
ing of  a  j)liable  piece  of  whalebone,  having 
a  sponge  tied  to  one  end.  The  operation 
being  determined  on  may  be  practised  stand- 
ing ;  if  the  swelling  be  large,  no  fear  need  be 
entertained  about  cutting  important  organs, 
as  the  enlargement  will  push  them  on  one 
side.  Cut  down,  therefore,  directly  upon 
the  centre  of  the  impacted  substance.  If 
the  horse  be  cast,  which  is  quite  unnecessary, 
have  him  of  course  thrown  with  his  left  side 
uppermost.  It  w^ill  also  be  necessary  to 
command  a  good  light.  The  part  of  the 
neck  chosen  for  the  opening  must  of  course 
be  governed  by  the  obstructing  mass.  A 
section  should  be  made  through  the  integu- 
ments and  cellular  tissue  beneath  them, 
right  into  the  oesophagus,  if  possible  with 
one  cut,  and  into  the  centre  of  the  pipe.  K 
this  be  not  done  at  once,  and  it  requires  some 
dexterity  so  as  to  effect  it,  mind  to  make  aU 
future  incisions  in  a  line  with  the  first  open- 
ing ;  as  it  is  important  that  the  cellular  tis- 
sue should  be  little  interfered  with.  The 
oesophagus,  fairly  cut  into  the  impactment, 
should  jump  forth ;  should  it  not  do  so,  do 
not  manipulate,  or  attempt  to  force  it  out, 
but  enlarge  the  opening,  and  the  substance 
will  come  through  when  that  is  long  enough ; 
but  no  fingering  could  compel  its  exit  while 
the  opening  is  too  small.  The  end  gained 
for  which  the  incision  was  made  in  the 
oesophagus,  the  wound  may  be  then  closed 
by  the  interrupted  sutures,  each  holding  a 
small  piece  of  tow  above  the  orifice,  and 
having  their  ends  hanging  out  of  the  exter- 
nal opening,  which  should  also  be  brought 
together  by  sutures.  The  after-treatment 
should  be,  to  interdict  aU  dry  food  ;  the  ani- 
mal ought  to  subsist  on  very  thick  gruel  for 
three,  four,  or  five  days.  If  the  condition 
appears  to  suffer  much,  allow  malt  mashes, 
and  when  so  doing  watch  the  wound  ;  and 
if  the  matters  taken  in  are  seen  to  ooze  out, 
wash  them  away  frequently  with  warm 
water,  to  prevent  lodgment,  which  might 
encourage  sinuses  to  form ;  and  after  each 


A  DICTIONAEY. 


269 


washing,  syringe  with  some  very  mild  stimu- 
lant, as  a  very  weak  solution  of  sulphate  of 
zinc  {white  vitriol),  etc.  etc. 

"  Neurotomy.  —  Division  of  the  sentient 
nerves  of  the  foot.  —  Neurotomy  has  now 
stood  the  test  of  very  extensive  application : 
our  writers  offer  innumerable  proofs  of  its 
restoring  almost  useless  animals  to  a  state 
of  much  utility.  And,  if  there  are  chances 
that  it  may  occasion  such  injury  as  to 
hasten  the  end  of  some  horses,  it  is  usually 
in  such  as  the  disease  would  have  done  the 
same  for  at  no  distant  period.  Having 
stated  thus  much  in  its  favor,  it  must  not 
be  supposed  that  we  recommend  it  as  an 
unqualified  benefit,  even  where  it  succeeds 
best.  No  neurotomized  horse  ever  after 
goes  with  the  same  freedom,  nor  with  equal 
safety,  as  he  did  before  the  operation  was 
performed  :  indifference  to  the  nature  of  the 
ground  gone  over,  is  said  to  have  fractured 
legs ;  it  is  quite  common  to  batter  the  feet 
to  pieces  ;  and,  although  horses  have  hunted 
afterwards,  and  hackneys  have  carried  their 
riders  long  distances,  yet  it  is  more  calcu- 
lated to  prove  beneficial  to  carrriage  than 
to  saddle  horses.  This  we  believe  to  be  a 
just  statement  of  its  merits ;  but  there  are 
benefits  which  it  offers  to  the  animal  of  a 
more  extensive  and  constitutional  kind. 
Those  gained  by  the  bodily  system  gener- 
ally have  been  in  some  cases  very  marked: 
thus,  an  aged  and  crippled  stallion,  from  the 
irritation  constantly  kept  up,  became  so 
emaciated  as  to  be  unable  to  fecundate ; 
but,  being  relieved  from  a  constant  state  of 
suffering  by  neurotomy,  improved  in  health 
and  condition,  and  was  again  used  to  cover. 
It  happened,  also,  that  a  mare  similarly  cir- 
cumstanced ceased  to  feel  oestrum ;  but 
after  neurotomy  it  again  returned,  and  she 
resumed  her  character  of  a  brood  mare.  It 
appears  to  act  with  most  certainty  when  a 
portion  of  the  irritated  nerve  is  excised. 
One  case  has  actually  occurred  where  the 
tetanus,  occasioned  by  a  wound  in  the 
foot,  was  arrested  and  removed  by  neuroto- 
my. It  also  promises  much  in  the  painful 
state  of  some  cankers,  where  the  irritation 
has  rendered  the  application  of  dressings 


almost  impossible :  here,  by  depriving  the 
foot  of  sensibility,  we  deprive  the  horse  of 
that  which  is  injurious  to  him :  the  sore  it- 
self is  often  amended  by  it ;  but  in  every 
instance  the  dressings  can  be  effectively 
applied,  and  the  healthy  processes  cannot 
be  at  all  suspended. 

"  With  respect  to  wherther  the  lower  or 
upper  incision  ought  to  have  the  preference, 
the  decision  should  be  guided  by  the  cir- 
cumstances, as  regards  the  intensity  and 
the  seat  of  the  disease.  The  operation 
commonly  leaves,  for  a  considerable  time, 
some  enlargement  around  the  spot,  the 
effects  of  the  adhesive  matter  interposed 
between  the  severed  portions  of  nerve  ;  and 
which  can  be  remedied  by  no  application 
of  bandages.  This  bulging  remains  so 
long  as  life  continues ;  and,  however  cun- 
ningly the  incision  be  concealed,  this  can 
be  felt  with  ease,  and  tells  the  truth  ever 
after  the  operation  has  been  performed. 
Such  a  circumstance  has,  however,  led 
some  practitioners,  when  it  has  been  wished 
to  make  the  upper  section,  and  yet  to  avoid 
the  chance  of  detection,  to  operate  on  the 
metacarpal  nerve  on  the  outside,  and  on  the 
pastern  or  plantar  nerve  on  the  inside. 

'■'■Mode  of  performing'  the  operation. — The 
situation  of  the  section  through  the  skin 
being  determined  on,  a  guide  to  which  may 
be  gained  from  the  perforatus  tendon,  and 
having  firmly  secured  the  leg  to  be  first 
operated  on,  cut  the  hair  from  the  part. 
This  being  done,  and  the  exact  course  of 
the  artery  being  ascertained  by  its  pulsa- 
tion, make  a  section  close  to  the  edge  of 
the  flexor  tendon.  Let  the  cut  be  near,  but 
rather  behind,  the  artery,  if  below  the  fet- 
lock joint.  The  cellular  substance  being 
cleared  away  will  bring  the  vessels  into 
view,  and  the  nerve  will  be  readily  dis- 
tinguished from  them  by  its  whiteness. 
Elevating  it  from  the  vessels,  and  its  mem- 
branous attachments,  by  means  of  a  crooked 
needle  armed  with  thread,  pass  a  bistoury 
under  it,  as  near  to  the  upper  angle  of  the 
section  as  possible.  The  violent  spasm  the 
division  of  the  nerve  produces  may  be 
somewhat  lessened  by  pressing  the  nerve 


270 


A  DICTIONARY. 


between  the  finger  and  the  thumb ;  when 
an  opportunity  may  be  taken,  either  with 
the  scalpel  or  scissors,  of  dividing  it ;  then, 
taking  hold  of  the  lowermost  portion  be- 
tween a  pair  of  forceps,  excise  about  three- 
fourths  of  an  inch  of  its  trunk.  Having 
finished,  if  both  feet  are  affected,  proceed 
to  operate  upon  the  contrary  side  of  the 
other  leg ;  after  'which  turn  the  horse,  and 
repeat  the  operations  on  the  like  parts  of 
each  leg  as  they  come  in  succession.  The 
integuments  may  be  now  drawn  neatly 
together,  and  secured  by  a  twisted  suture, 
the  whole  being  properly  covered  by  a 
light  compress.  Tie  up  the  head  for  a  day 
or  two,  after  which  put  on  a  cradle  ;  keep 
the  horse  very  quiet  and  low  ;  give  mashes 
to  open  the  bowels ;  but  we  should  avoid 
physicking^  from  the  fear  that  griping  might 
occur,  which  would  make  him  restless,  or 
probably  require  exercise. 

"  Periosteotomy. —  This  operation  consists 
in  having  the  horse  thrown  upon  his  side, 
and  the  leg  to  be  operated  upon  released 
from  the  hobble,  and  extended  upon  a  sack 
filled  with  refuse  hay  or  straw :  this  is  done 
by  means  of  a  piece  of  webbing  passed 
round  the  hoof,  and  the  end  given  to  a  man 
to  hold,  who  pulls  rather  violently  at  the 
member.  The  operator  then  kneels  down 
and  feels  for  the  exostosis  he  intends  to  per- 
form periosteotomy  upon.  This  may  be  a 
splint  or  a  node,  and  commonly  exists  upon 
the  metacarpal  portion  of  the  fore  limb. 
The  operator  having  found  the  excrescence, 
snips  just  below  it  with  a  pair  of  rowelling 
scissors.  He  then  takes  a  blunt  seton  nee- 
dle and  drives  it  through  the  cellular  tissue, 
and  immediately  over  the  enlargement. 
Next,  another  slit  in  the  skin,  above  the 
exostosis,  is  made  with  the  rowelling  scis- 
sors, and  through  this  last  opening  the 
point  of  the  seton  needle  is  forced  and  then 
withdrawn.  Lito  the  free  space  thus  made 
a  curved  knife  is  introduced :  the  point  of 
this  knife  is  blunt,  and  the  blade  curves  up- 
ward, the  cutting  part  being  below.  Some 
persons  use  a  very  diminutive  blade,  but  the 
editor  prefers  a  rather  large  instrument,  as 
being  more  under  the  command  of  the  hand. 


Having  introduced  this  knife,  he  turns  the 
cutting  edge  downward,  and  with  it  incises 
the  enlargement,  sending  the  blade  right 
through  the  periosteum,  and  also  through 
the  substance  of  the  exostosis,  if  it  be  not 
too  solid  for  the  knife  to  penetrate.  This 
latter  fact  is  only  to  be  ascertained  by  ac- 
tual experience,  and  no  opinion  formed 
after  an  external  examination  can  be  of  any 
value  ;  such  being  much  more  the  guess  of 
a  pretender  than  the  judgment  of  a  surgeon. 
The  age  of  the  animal  may  be  some  guide, 
but  even  this  it  is  better  not  to  depend  upon 
too  entirely.  It  is  true  that  young  horses 
freely  cast  forth  exostoses,  which  aged  ani- 
mals mostly  absorb ;  but  this  rule,  though 
very  general,  has  exceptions,  and  by  no 
means  is  to  be  absolutely  depended  upon. 

"  The  enlargement  being  cut  through,  next 
take  a  seton  needle  armed  with  a  tape,  and 
draw  it  through  the  channel  already  made : 
tie  a  knot  at  either  end  of  the  tape,  large 
enough  to  prevent  its  being  pulled  through 
the  opening  at  either  end,  and  the  business 
is  over.  The  affair  is  very  simple,  and  the 
horse  may  be  at  once  let  up.  It  is,  how- 
ever, in  some  cases,  and  only  in  some,  of  so 
much  benefit  that  the  horse,  being  thrown 
'  dead  lame,'  gets  up  and  trots  off  quite 
sound.  However,  ere  you  adopt  the  opera- 
tion, apprise  the  owner  of  the  risk  incurred, 
and  that  it  is  by  no  means  a  certain  cure. 
Leave  the  choice  with  him,  but  be  sure  and 
tell  him  the  openings  made  for  the  entrance 
and  exit  of  the  seton  commonly  leave  a 
blemish  behind  them  ;  and  where  the  seton 
travelled,  often  there  remains  a  thickening, 
which  it  may  require  months  to  obliterate. 

"  The  after  part  of  the  treatment  consists 
in  merely  having  the  seton  daily  moved  to 
and  fro :  though  some  persons  apply  an 
active  blister  all  over  the  parts  immediately 
in  the  neighborhood  of  the  seton ;  under 
the  idea  that  the  vesicatory  renders  the 
operation  of  greater  efficacy,  which  how- 
ever is  very  questionable.  When  perioste- 
otomy acts  at  aU,  it  mostly  does  so  at  once ; 
and  when  its  benefits  are  not  immediate,  it 
is  better  to  withdraw  the  seton  to  prevent 
after  blemish,  rather  than  hazard  further  and 


A   DICTIONARY. 


271 


useless  treatment  by  the  application  of  a 
stimulant  to  skin  already  deprived  of  any 
connection  with  the  deeper  seated  structures. 

'■'■Division  of  the  flexor  tendon.  —  There 
are  so  many  accidents  and  diseases  that 
may  produce  contraction  of  the  flexor  ten- 
dons, that  we  only  wonder  we  do  not  more 
often  meet  with  them ;  which  we  should 
certainly  do,  but  that  the  attendants,  de- 
spairing of  being  able  to  aflbrd  relief,  ad- 
vise their  destruction.  The  operation  con- 
sists in  making  a  longitudinal  incision  of 
about  three  inches  in  length  along  the  inner 
lateral  edge  of  the  tendon ;  dissecting  each 
portion  from  its  cellular  attachments,  so  as 
to  expose  the  nerve,  artery,  and  tendons. 
This  opening  will  allow  the  perforans  to  be 
freed  from  the  perforatus,  when  a  division 
should  be  made  by  a  scalpel  applied  to  its 
surface.  It  is  evident  that  this  should  take 
place  below  any  thickening,  or  adhesions 
which  may  have  permanently  connected  the 
tendon  with  the  neighboring  parts;  any 
lesser  attachments  will  be  broken  through, 
by  forcing  back  the  foot  to  the  just  position. 
By  Mr.  Dick  this  was  done  'by  placing  his 
knee  against  the  front  or  projecting  part  of 
the  pastern,  at  the  same  time  laying  hold 
of  the  foot  with  one  hand  and  the  upper 
part  of  the  leg  with  the  other,  and  using 
considerable  force  :  and  this  appears  to  be 
necessary,  in  order  to  break  any  adhesions 
that  may  have  formed.'  The  limb  should 
now  be  placed  in  a  poultice ;  and,  if  any 
fear  of  future  contraction  should  arise  dur- 
ing the  cure,  lengthen  the  toe  of  the  shoe 
proper  to  the  foot  operated  on.  Some  slow 
exercise  after  the  first  week  may  be  allowed, 
but  previously  to  that  the  horse  should  be 
confined  to  a  stall,  during  which  the  bowels 
must  be  kept  open  with  mashes. 

'■^Amputations.  —  These  have  been  hitherto 
confined  principally  to  the  tail,  the  ears,  and 
other  parts  of  minor  importance  in  the 
animal  frame ;  but  veterinary  surgery  now 
takes  a  wider  field,  and  the  extremities  are 
amputated  with  a  certainty  of  making 
horned  cattle  still  serviceable  for  the  pru- 
pose  of  yielding  milk ;  and,  without  doubt, 
the   same   might  be  done  with  the  brood 


mare,  or  stallion,  particularly  in  fractures 
of  the  fore  extremities.  Professor  Dick,  of 
the  Edinburgh  Veterinary  College,  fm-nishes 
a  case  sent  to  him  by  one  of  his  pupils,  to 
the  following  effect :  '  I  performed  amputa- 
tion upon  the  cow  on  the  7th  of  July ;  after 
having  properly  secured  the  animal,  and 
applied  a  tourniquet  above  the  carpus,  I 
made  a  cucular  incision  through  the  integ- 
uments round  the  leg,  a  little  below  the 
carpus ;  and,  having  separated  the  skin  so  as 
to  allow  of  its  being  pushed  up  a  little,  I 
cut  through  the  sinews,  and  lastly  sawed 
off  the  stump :  the  parts  are  now  com- 
pletely whole,  although  she  has  been  going 
at  grass  all  the  time ;  and,  now  that  she  has 
got  the  advantage  of  a  cork  stump,  makes 
a  wonderful  shift  for  herself,  and  yields  a 
good  supply  of  milk  to  her  owner.'  Mr. 
Dick  also  notices  another  case  of  amputation 
of  the  fore  leg  of  a  two-year-old  heifer ;  and 
of  a  third,  where  the  hind  leg  was  removed 
above  the  tarsus.  Such  operations  have 
occasionally  occurred  from  time  immemo- 
rial, with  a  few  enterprising  characters. 
We  have  heard  of  them,  but  they  were 
mostly  regarded  as  mere  matters  of  curiosity 
or  wonder ;  and  therefore  were  not  imitated. 
We  shall,  however,  probably  ere  long  have 
them  more  common,  in  cows  at  least ;  for, 
occurring  below  the  carpus  and  tarsus,  they 
are  as  easily  performed  as  nicking  or  dock- 
ing :  and  there  is  no  doubt  but,  were  a  hol- 
low padded  stump  applied,  such  low  opera- 
tions might  be  prudent  in  many  cases. 
Fractures,  with  great  comminution  of  bone, 
considerable  ravages  of  disease  within  the 
foot,  or  extensive  gangrene,  are  the  cases 
which  might  call  for  amputation.  Of  the 
method  of  amputation  little  need  be  added 
to  the  above.  The  principal  practical  points 
are,  the  fixing  of  a  tom'niquet  of  sufficient 
force,  which  should  be  padded  to  make  its 
principal  pressure  on  the  leading  arterial 
trunks,  while  its  general  circumference  will 
act  on  the  smaller  vessels :  a  ring  should  be 
cut  lightly  below  the  intended  place  of  opera- 
tion, only  through  the  integuments  ;  which, 
when  separated  from  their  cellular  ad- 
hesions  for   about   six    inches,   should   be 


272 


A   DICTIONARY. 


turned  back ;  and  a  circular  incision  may 
then  be  made  through  the  muscles,  etc., 
taldng  up  by  ligature  such  vessels,  both 
venous  and  arterial,  as  display  a  disposition 
for  much  ha:>morrhage.  The  section  thus 
made,  free  the  bone  from  the  soft  parts  by 
the  scalpel,  where  the  adherences  are  very 
intimate  ;  and  having  by  means  of  a  crucial 
bandage  retracted  the  soft  parts  altogether 
above  the  bone,  saw  it  through.  Finally, 
effectually  secure  the  principal  vessels, 
when,  bringing  the  soft  parts  and  skin  over 
the  bone,  retain  them  there  by  proper  band- 
aging, which  suffer  to  remain  without  dis- 
turbance until  the  thu*d  or  fourth  day. 

'■'■Amputation  of  the  Penis.  —  Amputation 
of  the  penis  is  not  unknown  among  us :  it 
has  been  performed  several  times,  and  it  is 
found  that  no  canula  is  necessary  to  keep 
open  the  urethra :  the  force  of  the  urinary 
flow  breaking  down  any  incipent  cicatriza- 
tion of  its  orifice.  The  sheath  is  first  forced 
back,  and  the  penis  brought  forward  to  its 
greatest  possible  extent:  whatever  portion 
it  is  intended  to  remove  is  now  cut  through 
by  means  of  an  amputating  knife;  when 
the  remainder  is  retracted  within  the  sheath, 
and  little  haemorrhage  has  afterwards  oc- 
curred, except  at  the  time  of  passing  the 
urine  ;  but  there  appears  to  have  been  no 
alarming  quantity  of  blood  lost. 

^^ Amputation  of  the  Tail,  or  Docking-.  — 
We  are  most  happy  to  state  this  filthy  and 
unnecessary  operation  is  now  discarded.  It 
never  consisted  of  more  than  the  cutting  off 
a  portion  of  the  stump  with  brute  force,  and 
the  cruel  application  afterwards  of  a  hot 
iron  to  the  small  artery  of  the  tail. 

"  Nicking'.  — We  should  be  grateful  that 
this  barbarous  and  dangerous  process  is  no 
longer  numbered  among  the  necessary  oper- 
ations. It  is  so  beset  with  accidents  which 
no  skill  or  prudence  can  prevent,  that  no 
one  who  has  a  free  will  ought  to  mutilate  a 
horse  by  nicking. 

'■'■Firing.  —  The  practice  of  firing  was  not 
always  confined  to  quadrupeds  ;  on  the  con- 
trary, it  probably  was  first  used  on  man ; 
and  to  this  day  in  many  countries  it  is  a 
very   popular  remedy   among  human  sur- 


geons. In  India  it  is  applied  over  the  abdo- 
men for  the  cure  of  scirrhosity  of  the  liver. 
Firing  in  veterinary  practice  has,  by  Mr. 
Coleman's  pupils,  been  justified  as  only  men 
will  justify  a  favorite  operation,  the  virtues 
of  which  have  been  impressed  upon  their 
minds  by  an  eloquent  teacher.  When  Cole- 
man was  the  chief  of  the  veterinary  profes- 
sion, fuing  under  his  rule  was  used  for  any 
and  every  occasion.  It  was  ridiculously 
supposed  to  act  as  a  permanent  bandage  ;  as 
if  a  few  strokes  with  a  heated  iron  could 
destroy  the  elastic  property  inherent  in  the 
skin.  It  was  the  favorite  styptic  of  these 
practitioners,  and  was  applied  to  arteries  (as 
of  the  tail),  as  though  it  possessed  within 
itself  some  medicinal  virtue.  It  was  used 
to  promote  absorption,  as  in  callus ;  and  was 
lilcewise  resorted  to  to  check  absorption,  as 
in  ulceration.  It  was  called  into  action  to 
promote  granulation,  in  broken  knees  ;  and 
was  also  a  favorite  agent  to  check  granula- 
tions, when  they  were  too  luxm-iant.  In 
short,  there  was  no  folly  which  a  hot  iron  did 
not  cover.  It  has  now  happily  fallen  into 
disuse.  Most  modern  practitioners  will 
now  confess  that  their  chief  reason  for  exer- 
cising the  iron  is  to  satisfy  the  proprietor, 
not  to  benefit  the  animal.  After  such  an 
acknowledgment,  who  would  submit  to  have 
his  patient  servant's  skin  scored  and  burnt 
with  red  hot  metal  ? 

"  The  mode  of  cauterization  differs  accord- 


ing to  circumstances. 


As  a  general  rule  it 


ought,  of  course,  to  be  applied  in  the  direc- 
tion of  the  hair,  by  which  the  blemish  is 
lessened :  but  this  rule  cannot  be  arbitrarily 
followed,  although  it  ought  to  do  away  with 
all  the  false  pride  of  displaying  the  taste  in 
the  figures  scored  upon  a  prostrate  beast. 
The  Veterinary  College  recommends  that 
the  limbs  be  always  fired  in  perpendicular 
lines ;  others  advocate  all  manner  of  fanci- 
ful marks.  Some  cast  the  horse ;  many 
surgeons  perform  standing.  The  irons  used 
are  of  various  shapes  and  dimensions. 
Some  recommend  the  firing  of  all  things  to 
be  very  light ;  others  persist  there  is  no  vir- 
tue in  hot  iron  unless  it  burns  very  deep. 
The  operation  consists  in  having  irons  of 


A  DICTIONARY. 


273 


some  substance  made  red  hot,  and  tlien 
drawing  them  mechanically  along,  or  twist- 
ing them  about  upon  the  sldn.  The  figures 
are  various,  so  is  the  depth  of  the  incision. 
Both  must  be  decided  by  the  taste,  judg- 
ment, or  heartlessness  of  the  operator. 

^'■Blistering. — This  is  an  operation  of  very 
great  utility,  and  is,  perhaps,  compared  with 
its  benefits  and  importance,  the  safest  that 
is  performed.  When  a  vesicatory  becomes 
absorbed  through  the  pores  of  the  skin,  it 
inflames  the  sensible  cutis  underneath ;  the 
consequence  of  which  is,  an  effusion  of  serum 
through  the  part,  which,  in  the  human  sub- 
ject, elevates  the  cuticle  into  a  bladder  equal 
to  the  sm-face  inflamed,  but  in  the  horse,  from 
the  greater  tenacity  of  the  cuticular  connec- 
tions, it  becomes  separated  in  the  form  of 
small  distinct-vesicles  only.  If  the  irritating 
cause  be  quickly  removed,  the  serum  may  be 
re-absorbed,  and  the  surface  restored  by  a 
slight  effort  of  adhesive  inflammation.  If 
the  irritant  act  in  a  still  minor  degree,  it  sim- 
ply irritates  the  vessels  of  the  cutis  to  an  in- 
filtration of  fluid  through  the  sensible  pores, 
but  produces  no  desquamation  of  cuticle : 
such  has  been  called,  a  sweating  blister. 
But  when,  by  continued  irritation,  the  cutis 
is  exposed,  suppuration  succeeds,  and  the 
part  is  fully  blistered.  The  salutary  action 
of  blisters  is  exerted  in  several  ways  ;  in  pro- 
moting absorption ;  in  combating  deep- 
seated  inflammations,  and  in  aiding  others. 
As  a  stimulus  to  the  absorbents,  they  act 
beneficiaUy  in  the  removal  of  injmuous 
deposits,  as  the  coagula  remaining  after 
inflammatory  lessons.  But  it  is  to  be  re- 
marked, that  when  any  existing  deposit  is  of 
long  continuance,  or  is  osseous,  it  requires 
that  the  action  of  the  vesicatory  be  kept  up. 
Mercurial  blisters  have  been  thought  to  have 
a  superior  influence  in  accelerating  absorp- 
tion. Mercurials,  rubbed  in  some  weeks  or 
days  previously  to  blistering,  are  certainly 
great  assistants,  and  should  always  be  em- 
ployed in  the  treatment  of  obstinate  osseous 
or  ligamentry  enlargements.  Blisters  are 
very  important  aids,  in  inflammatory  affec- 
tions, as  counter-h-ritants,  derived  from  a  law 
in  the  animal  economy,  that  two  inflamma- 


tions seldom  exist  in  the  vicinity  of  each 
other  ;  therefore,  when  such  an  affection  has 
taken  place  in  any  part,  and  we  wish  to  re- 
move it,  we  attempt  to  raise  an  artificial  in- 
flammation in  the  neighborhood  by  means 
of  blisters ;  which,  if  persevered  in,  destroy, 
or  at  least  lessen,  the  original  one.  Occa- 
sionaUy  also  we  blister  the  immediate  in- 
flamed part,  with  an  intention  to  hasten  the 
suppurative  process  by  increasing  the  ac- 
tivity of  the  vessels;  as  in  deep-seated  ahr 
scesses  and  also  in  those  which  attack  glan- 
dular parts.  We  therefore  employ  blisters, 
to  hasten  the  maturation  of  the  tumors  in 
strangles.  When  the  flagging  powers 
vaciUate  between  resolution  and  suppura- 
tion, as  they  often  do  in  the  phlegmonous 
inflammations  of  glandular  or  of  deep- 
seated  parts,  blisters  may  either  hasten  the 
resolution,  or  they  may  add  their  influence 
to  the  attempted  suppuration,  and  thus 
bring  it  to  maturity.  But  we  carefuUy 
avoid,  in  other  cases,  applying  a  vesicant  to 
a  part  immediately  in  a  state  of  active  in- 
flammation :  particularly  we  should  avoid 
what  is  too  often  done,  that  of  blistering 
over  the  tendons,  ligaments,  and  articula- 
tory  surfaces  of  a  tumid  limb,  laboring 
under  a  congested  state  of  the  parts  from 
excess  of  vascular  action.  Here  we  should 
do  great  injury  were  we  to  blister,  by  caus- 
ing a  greater  deposit  of  lymph,  and  by  has- 
tening its  organization  into  an  injurious 
bond  of  union  between  the  inflamed  parts. 
The  vesicatory  or  blister,  for  general  use  in 
veterinary  medicine,  as  a  simple  stimulant, 
should  be  principally  composed  of  Spanish 
flies.  Cheaper  substitutes  are  used,  but 
they  irritate  violently :  in  extensive  inflam- 
matory affections,  they  are  on  this  account 
perfectly  inadmissible ;  and  wherever  a  case 
requires  anything  more  it  will  be  noted. 
The  mode  of  blistering  with  the  Spanish 
fly  is  sufficiently  known.  The  hair  should 
be  cut  or  shorn  as  close  as  possible  from 
around  the  part ;  the  blistering  matter 
should  then  be  well  rubbed  in  for  ten  or 
fifteen  minutes.  If  the  pasterns  and  fet- 
locks are  the  parts  to  be  blistered,  previous 
to  rubbing  in  the  ointment,  smear  some  lard, 


274 


A    DICTIONARY. 


tallow,  or  melted  suet,  over  the  heels,  and 
within  the  hollow  at  the  back  of  "the  small 
pastern.  This  wiU  often  prevent  some 
troublesome  sores  forming,  from  the  blister- 
ing ointment  falling  on  these  sensitive  parts. 
While  a  blister  is  acting,  the  litter  should 
be  removed  from  under  the  feet,  or  it  will 
tickle  the  legs,  and  imtate ;  but,  above  all, 
the  head  ought  to  be  most  carefully  secured, 
for  two  days  and  nights,  to  oppose  lying 
down,  more  especially  to  prevent  the  horse 
biting  the  blistered  part.  On  the  third 
evening  he  may  be  permitted  to  repose ; 
but  a  prevention  should  even  then  be  con- 
tinued, by  means  of  what  is  called  a  cradle. 
This  apparatus  may  be  bought  at  every 
turning  shop ;  or  may  be  made  of  eight  or 
ten  pieces  of  round  wood,  an  inch  and  a 
half  in  diameter,  and  two  feet  long :  these 
are  strung  at  each  end  on  a  rope,  and  fas- 
tened around  the  neck.  When  it  is  in- 
tended to  blister  repeatedly,  the  eflects  of 
the  first  should  have  subsided  before  the 
second  is  applied :  the  scm-f  and  scabs  also 
be  cleared  away,  and  the  part  well  washed 
with  soap  and  water.  In  aU  cases,  the  third 
or  fourth  day  after  the  application  the  part 
should  be  thoroughly  painted  over  by 
means  of  a  long  haired  brush  (such  as  are 
in  use  with  pastry-cooks  to  glaze  their 
crusts)  with  lead  liniment,  which  should  be 
repeated  every  day ;  and  when  it  is  proposed 
to  turn  a  horse  out,  it  should  never  be  done 
until  the  whole  blistered  sm-face  be  quite 
healed ;  otherwise  dirt,  flies,  etc.,  may  prove 
hurtful.  It  remains  to  observe,  that,  instead 
of  repeated  active  blistering,  it  is  in  some 
cases  preferable  to  keep  up  a  continual 
slight  irritation  on  the  original  blister  by 
means  of  stimulants,  as  iodine  ointment, 
mild  blistering  applications,  etc. ;  caution  is 
however  necessary  to  avoid  forming  an 
eschar,  and  thereby  a  permanent  blemish ; 
but  when  a  blemish  is  not  of  consequence 
this  plan  will  be  found  often  more  effica- 
cious than  firing,  as  in  splints,  spavins,  etc. 
Some  practitioners  blister  mildly  one  day, 
and  on  the  next  wash  off  the  blistermg 
matter,  thereby  saving  loss  of  hair.  But 
there  is  more  of  apparent  than  real  good  in 


this  plan.  If  a  blister  be  necessary,  it  re- 
quires all  its  activity. 

'■'■  Ammoniacal  blister. —  Spanish  flies  are 
only  efficacious  when  the  animal  can  afford 
to  wait  their  action,  which  is  rather  slow. 
In  most  of  the  acute  diseases,  the  horse 
would  perish  before  the  blister  began  to 
rise,  wherefore  resort  has  been  had  to  boil- 
ing water  and  red-hot  iron.  The  action  of 
these  last  coarse  and  brutal  measures  was 
alone  controlled  by  the  violence  of  the  in- 
ternal inflammation ;  and,  if  the  practitioner 
was  mistaken  in  his  estimate  of  the  imme- 
diate danger,  extensive  and  lasting  blemish 
was  the  consequence.  We  have  in  the 
liquor  ammonia  an  agent  quite  as  formida- 
ble as  boiling  water  or  heated  iron,  but  it  is 
rather  longer  in  displaying  its  force ;  where- 
fore, it  allows  time  for  watching  its  action, 
and  of  checking  it  the  instant  it  has  suffi- 
ciently blistered  the  skin.  It  is  true  the 
liquor  ammonia  upon  the  skin  cannot  be 
removed,  neither  need  it  be  counteracted. 
Ammonia  is  like  steam,  only  powerful 
when  confined.  The  ordinary  soap  lini- 
ment, if  covered  over,  would,  because  of  the 
ammonia  it  contains,  produce  a  lasting 
blemish;  but  every  veterinary  surgeon  knows 
how  very  harmless  a  preparation  that  is 
when  simply  rubbed  upon  the  surface.  So, 
when  we  desire  the  active  effects  of  liquor 
ammonia,  we  double  a  blanket  or  rug  four 
or  five  times  and  hold  it  over  the  liquid. 
It  takes  from  ten  to  twenty  minutes  to  raise 
a  blister,  and  it  consequently  can  from  time 
to  time  be  observed ;  and,  when  its  action 
has  reached  the  wished-for  point,  all  we 
have  to  do,  effectually  to  stop  it,  is  to  take 
away  the  rug  or  blanket.  That  removed, 
the  free  surface  and  the  heat  of  the  body 
occasions  the  ammoniacal  vapor  to  be  dis- 
persed, and  the  animal  is  safe. 

"  RoivelUng: —  Rowels  act  as  foreign  sub- 
stances within  the  body ;  they  cause  irrita- 
tion and  suppuration,  whereby  more  deep- 
seated  inflammations  are  '  supposed  to  be 
removed ;  they  are,  however,  often  very 
convenient,  because  they  stand  as  sign- 
boards to  sliow  the  proprietor  that  some- 
thing has  been  done.     The  common  mode 


A   DICTIONARY. 


275 


of  making  a  rowel  is  after  the  following 
manner :  a  slit  is  first  made  by  means  of 
the  rowel  scissors,  on  any  part  of  the  integ- 
uments held  between  the  finger  and  thumb; 
with  the  handle  of  the  scissors  separate 
fi-om  its  cellular  connections  a  circle  of  two 
or  three  inches  in  diameter,  into  which  in- 
troduce something  to  prevent  the  reunion 
of  the  skin.  A  piece  of  circular  leather, 
tolerably  stiff",  with  a  central  hole,  is  a  very 
common  substance  used,  but  is  objected  to 
by  some  on  account  of  the  difficulty  of 
changing  it  without  injuring  the  skin :  tow, 
as  more  pliant,  is  frequently  introduced  into 
this  cavity.  If  the  rowel  runs  freely,  it 
should  be  dressed  every  day,  by  changing 
the  plug,  if  of  tow,  and  by  cleansing  it,  if 
of  leather.  No  rowel  should  go  undressed 
beyond  the  second  day,  for  the  comfort  of 
the  horse.  They  are  very  favorite  applica- 
tions with  farriers,  and  therefore  are  fre- 
quently abused,  by  being  employed  in  all 
cases  indiscriminately ;  they  are  now,  how- 
ever, falling  into  disuse,  setons  having  almost 
superseded  them. 

"  Setons,  in  their  action,  resemble  a  very 
mild  form  of  rowel,  but  are  more  conven- 
ient in  their  application.  There  is  hardly 
a  part  of  the  body  where  a  seton  may  not 
be  conveniently  placed :  they  have  been  put 
around  the  eye  ;  they  have  also  been  entered 
at  the  withers,  and  brought  out  between 
the  humerus  and  the  sternum,  —  so  exten- 
sive or  so  diminutive  can  they  be  made. 
In  sinuous  ulcers  of  the  withers  and  of  the 
neck,  they  may  be  placed;  through  the 
heels,  in  foot  diseases,  they  have  been  in- 
serted. In  cavernous  sores,  they  are  en- 
tered at  the  superior  part,  and  are  brought 
out  at  an  inferior,  so  as  to  form  a  depending 
orifice.  The  formation  of  a  seton  is  very 
simple :  a  skein  of  thread,  or  a  piece  of  tape 
of  a  convenient  size,  may  be  used :  at  the 
one  end  place  a  large  knot;  arm  the  eye 
of  a  corresponding-sized  seton  needle  with 
the  free  end  of  the  tape ;  introduce  this  into 
any  proposed  part,  and,  bringing  it  out  at 
some  other,  either  make  a  second  knot,  or 
tie  the  two  ends  of  the  tape  together ;  which 


last  method  of  fastening  is,  however,  often 
objected  to,  from  the  danger  of  its  catching 
in  something,  and  being  torn  out,  to  the 
disfigm-ement  of  the  horse.  When  a  seton 
is  placed  in  a  sinuous  track,  for  the  purpose 
of  inflaming,  it  is  moved  twice  a  day  fre- 
quently, and  moistened  each  time  with  some 
stimulant,  as  oil  of  turpentine,  tincture  of 
aloes  and  of  benjamin.  All  setons  require 
daily  cleaning  and  moving.  When  they 
are  required  to  act  more  quicldy,  the  tape 
is  infused  in  terebinthinate  of  cantharides, 
or  small  pieces  of  black  hellebore  are  sewn 
within  it.  An  old  material,  composed  of 
woollen,  flax,  or  cotton,  and  hair,  is  also 
used  instead  of  tape.  Setons,  however,  are 
of  small  service  in  acute  cases.  They  are 
chiefly  in  use  for  disturbances  of  a  chronic 
description. 

"  Abstraction  of  Blood,  or  Bleeding.  — 
Arteriotomy.  —  Blood  is  abstracted  by  open- 
ing the  conducting  vessels,  arterial  and  ve- 
nous. When  taken  from  arteries,  the 
process  is  called  arteriotomy ;  when  by  the 
latter,  phlebotomy.  Some  bleedings  include 
both  these  operations,  as  general  scarifica- 
tions of  the  soft  parts ;  bleeding  at  the  toe 
point ;  divisions  of  the  vessels  of  the  cornea, 
etc.,  etc.  Blood-letting  is  called  local  when 
it  is  practised  on  or  very  near  the  affected 
part ;  and  it  is  supposed  to  act  more  im- 
mediately than  general  bleeding,  because  it 
produces  more  effect  with  the  loss  of  less 
blood.  Local  bleeding  is  therefore  usually 
practised  on  the  minor  branches  of  the 
arteries  and  veins,  as  on  the  temporal  artery, 
the  plate  vein,  the  vena  saphena,  etc. 
Leeches  are  a  means  of  local  bleeding  not 
often  used  by  us  in  veterinary  practice ;  but 
there  is  no  reason  whatever  why  they  should 
not  be  employed ;  when  appUed  to  the  eye, 
and  occasionally  to  other  parts  also,  they 
adhere  readily,  abstracting  blood  rapidly, 
and  therefore  might  be  valuable  aids  in 
violent  local  inflammation.  Cupping  is 
also  practised  in  France  and  other  parts  of 
the  Continent  with  very  large  glasses,  and  it 
is  there  supposed  to  act  remedially  in  many 
local  inflammations.     By  general  bleeding 


276 


A   DICTIONARY. 


we  understand  the  depletion  of  the  system 
at  large ;  and  this  we  practice  in  extensive 
inflammations. 

"  Division  of  the  temporal  artery.  —  The 
proper  spot  for  either  its  puncture  or  divi- 
sion is  directly  where  the  vessel  leaves  the 
parotid  gland,  to  curve  upward  and  forward 
around  the  jaw,  a  little  below  its  condyle. 
When  it  is  puncttired,  it  usually  affords 
much  blood  ;  and  in  such  case,  enough  hav- 
ing been  obtained,  divide  the  trunk  ;  when, 
the  receding  portions  becoming  pressed  by 
the  integuments,  and  lessening  by  their 
own  contractility,  the  hemorrhage  is  stopped. 
It  should  be  punctured  by  a  lancet ;  a  fleam 
may  fix  itself  in  the  bone.  Its  division  can 
be  readily  made  also  either  by  a  lancet  or 
scalpel. 

"  Bleeding  by  the  palate  is  also  a  species 
of  arterio-phlebotomy,  and  is  a  very  favorite 
spot  for  abstracting  blood  with  most  igno- 
rant persons,who  vehemently  recommend  it 
in  spasmodic  colic  or  gripes,  and  in  megrims. 
In  such  cases,  however,  a  want  of  knowl- 
edge of  the  anatomy  of  the  parts  has  occa- 
sioned a  serious  hemorrhage  to  occur ;  it 
may  prove  a  fatal  one,  if  the  artery  proper 
to  the  part  be  divided  incompletely.     The 
palatine  artery  and   nerve   run   near  each 
other,  on  each  side  of  the  roof  of  the  mouth, 
so  as  to  divide  the  inner  surface  of  the  hard 
palate  into  three  nearly  equal  portions.     No 
other  than   a   direct   division   of  the  vein 
should  ever  be  made  :  therefore,  when  bleed- 
ing is  determined  on  at  this  place,  do  it  by 
plunging  a  lancet  or  even  a  penknife  in  a 
direct  line  across  the  ruges,  one  inch  within 
the  mouth,  exactly  betiveen  the  middle  and 
second  nippers ;  there  these  vessels  form  a 
curve,  which  curve  will  then  be  divided,  and 
wiU  then  yield  three  or  four  pints  of  blood. 
If  the  instrument  enter  too  much  on  one 
side,  as  about  the  middle  of  thp   second 
nipper,  then  a  partial  and  longitudinal  divi- 
sion  of  the  artery  may  be  made,  and  an 
alarming  hemorrhage  may  follow.     In  this 
case,  the  section  must  be  enlarged  and  deep- 
ened inwardly,  that  is,  away  from  the  teeth, 
which  completely  severs  the  vessel,  and  its 
retraction  wiU   stop   the   hemorrhage.      A 


moderate  or  slight  flow  of  blood  from  the 
palate  may  be  obtained  by  light  scarifica- 
tions of  the  ruga3 :  but  all  bleedings  here, 
except  under  circumstances  of  the  most 
urgent  necessity,  had  better  be  avoided. 

"  Bleeding  by  the  toe  is  also  arterior-phle- 
botomy.  By  no  means  cut  out  a  portion 
of  the  sole  at  the  point  of  the  frog,  which 
frequently  occasions  abscess  ;  but  with  a 
very  fine  drawing-knife  cut  down  exactly  in 
the  line  of  union  between  the  crust  and  the 
sole ;  then,  by  puncturing  the  part  with  a 
lancet,  a  vast  flow  of  blood  may  be  ob- 
tained, the  benefits  of  which  in  some  cases 
are  very  marked,  particularly  in  acute 
founder.  If  the  blood  should  not  flow  with 
sufficient  freedom,  place  the  foot  in  warm 
water :  the  bleeding  finished,  cover  the  punc- 
tm*e  with  some  tow  and  a  little  tar,  and 
lightly  tack  on  the  shoe.  There  are,  how- 
ever, other  methods  of  bleeding  from  the 
toe.  Mr.  Maver  uses  a  drawing-lmife 
with  a  long  curve,  so  that  one  sweep  of 
the  blade  may  cut  a  piece  out  of  the 
foot.  This  appears  to  us  bad  practice 
as  it  leaves  nature  a  space  to  fill  up, 
instead  of  a  simple  incised  wound  to  heal. 
Others  take  away  none  of  the  horn,  but 
merely  make  a  slit  through  the  outer  cover- 
ing on  to  the  vascular  portion  of  the  foot. 
The  flap  of  horn  they  hold  up  so  long  as 
they  desire  blood,  by  the  insertion  of  a  piece 
of  wood ;  and  when  they  have  obtained 
blood  enough,  they  take  out  the  wood  so  as 
to  let  the  horny  flap  down.  This  last 
method,  of  all  others,  appears  to  us  the 
easiest  and  the  best. 

"  Sometimes  the  plantar  vein  is  opened  as 
a  substitute.  Scarifications  are  also  occa- 
sionally practised,  which,  of  course,  divide 
both  venous  and  arterial  branches.  In 
France  extensive  scarifications  used  to  be 
made  into  indurations  before  the  suppura- 
tive process  had  commenced,  which  in  some 
cases  prevented  that  from  going  on ;  and 
the  remedial  ivounds  made  were  healed  by 
adhesive  inflammation,  or  by  healthy  gran- 
ulation; the  same  method  has  also  been 
occasionally  practised  here,  but  it  is  not 
now  often  attempted. 


A   DICTIONARY. 


277 


"  Phlebotomy,  or  the  puncture  of  a  venous 
branch,  is  the  most  usual  mode  of  drawing 
blood  in  veterinary  practice,  and  may  be 
employed  on  any  point  of  the  body ;  but 
some  vessels  are  much  more  frequently 
opened  than  others,  and  most  of  all  the 
jugular. —  Bleeding  by  the  thigh  vein.  The 
saphena  is  a  prominent  vein,  continued  from 
the  inner  part  of  the  hock,  and  may  be 
opened  by  the  fleam ;  but  with  much  greater 
safety  and  propriety  by  a  lancet.  The 
opposite  leg  being  held  up,  the  operator 
placing  himself  in  front  of  the  tliigh,  and 
steadying  himself  and  the  horse  by  placing 
one  hand  on  the  hock,  may  fix  the  vein 
with  the  little  finger  of  the  other ;  while  the 
lancet  held  between  the  thumb  and  fore 
finger  punctures  it.  This  vein  should  never 
be  opened,  save  upon  absolute  necessity,  as 
it  is  often  troublesome  to  pin  up.  A  horse 
has  been  cast  for  the  trivial  matter  of  stop- 
ping the  haemorrhage.  —  Bleeding  from  the 
plate  vein.  This  vein  is  frequently  opened 
to  abstract  blood  after  injuries  of  the  fore 
extremities. —  The  superficial  brachial  vein 
is  a  continuation  of  the  superficial  division 
of  the  metacarpal  veins,  and  in  the  passage 
upwards  receives  more  than  one  branch  ;  its 
principal  trunk  ascends  along  the  inner  side 
of  the  radius.  It  may  also  be  well  to  re- 
mark, that,  v/hen  ta]>ing  blood  from  the 
superficial  veins  of  the  arm  or  fore-arm,  if 
any  difficulty  is  experienced  in  obtaining  a 
sufficient  flow,  the  lifting  up  of  the  other 
leg,  by  throwing  the  muscles  of  the  punc- 
tured one  into  action,  will  force  the  blood 
from  the  inner  to  the  outer  set ;  and  an  in- 
creased quantity  may  be  obtained.  The 
plate  vein,  or  external  thoracic,  is  often 
opened,  as  it  emerges  from  behind  the  arm, 
and  is  pinned  up  without  any  difficulty. 

"  Bleeding  by  the  jugular  vein.  —  The  situ- 
ation of  this  important  vessel  is  well  known, 
but  its  internal  connections  are  not  so 
familiar,  though  such  knowledge  is  essen- 
tial to  the  uniform  safety  of  the  operation. 
The  horse  has  only  external  jugular  veins,  a 
right  and  a  left  one :  as  each  emerges  from 
the  chest,  it  is  found  deep-seated,  and  ap- 
proaching the  trachea ;  it  then  passes   for- 


wards in  company  with  the  external  carotid 
artery :  toward  the  middle  of  the  neck  it 
becomes  more  superficial,  and  is  now  dis- 
tinctly seen  progressing  rather  above  and 
without  the  carotid  artery  and  trachea,  or 
windpipe.  The  carotid,  therefore,  in  the 
future  course  of  the  jugular,  is  situated  a 
Httle  below  and  more  deep-seated  than  the 
vein.  The  jugular  is  also  separated  from 
the  carotid  by  a  slight  muscular  band,  de- 
rived from  the  levator  humeri.  Its  further 
track  is  marked  in  the  hollow  formed  by 
the  inferior  edge  of  the  levator  humeri, 
where  it  is  covered  by  the  panniculus  car- 
nosus  and  integuments  only  ;  when,  having 
nearly  reached  the  jaw,  it  makes  its  well- 
known  division  into  two  portions.  Bleeding 
by  the  jugular  is  usually  practised  with  a 
lancet  or  with  a  fleam.  The  proper  spot 
for  the-  puncture  may  be  found  anywhere 
between  two  inches  and  six  from  the  division 
of  the  vein :  this  latitude  is  here  mentioned, 
because  it  is  prudent  to  avoid  puncturing 
directly  over  a  former  bleeding-place,  known 
by  the  scar  and  enlargement :  it  should  also 
be  avoided  where  a  little  knot  in  the  course 
of  the  vein  will  sometimes  denote  the  exis- 
tence of  one  of  the  venous  valves.  But  in 
all  ordinary  cases,  where  these  hindrances 
do  not  appear,  operate  at  two  or  three 
inches  from  the  division  of  the  vein ;  which 
will  be  sufficiently  evident  when  it  is  pressed 
on  below  the  place  punctured.  Avoid 
operating  low  down  in  the  neck,  as  there 
the  vessel  is  deeper  seated,  and  near  to  im- 
portant parts. 

"  First  moisten  the  hair  and  smooth  it 
down ;  then,  steadying  and  enlarging  the 
vessel  with  one  hand,  with  the  other  plunge 
the  point  of  the  lancet  into  the  integuments, 
so  as  just  to  puncture  them  and  the  vein ; 
then,  by  a  slight  turn  of  the  wrist,  carry  the 
instrument  obliquely  forward  to  finish  the 
cut.  For  opening  the  smaller  veins,  the 
lancet  should  always  be  used.  In  all  but 
the  practised  hand,  the  fleam  is  the  safest 
for  bleeding  from  the  jugular ;  it  is  always 
prudent  to  have  the  eye  of  the  horse  cov- 
ered :  unless  the  eye  be  covered,  the  horse 
will  be  likely  to  ffinch  at  the  moment  of 


278 


A   DICTIONARY. 


the  stroke,  and  tlie  puncture  may  be  made 
in  any  place  but  where  we  wish.  The  hair 
being  fust  wetted  and  smoothed,  and  the 
fleam  being  retained  in  the  left  hand,  the 
unemployed  fingers  pressing  on  the  vein  so 
as  to  fix  and  swell  the  vessel ;  let  the  point 
rest  exactly  in  the  middle  of  the  swelling ; 
strike  the  fleam  suflficiently  hard  to  penetrate 
the  skin  and  vein.  A  blood-stick  is  prefer- 
able for  the  purpose  of  striking  the  fleam : 
there  is  a  vibration  between  two  hard  bodies 
when  they  meet,  which,  in  this  instance,  is 
favorable  to  a  quick  and  moderate  puncture 
of  the  vein.  After  the  vein  has  been 
opened,  moderate  pressure  with  the  edge  of 
the  can  which  catches  the  blood  is  sufficient 
to  keep  up  the  flow:  it  may  also  be  en- 
couraged by  putting  a  finger  within  the 
horse's  mouth.  The  requisite  quantity  of 
blood  being  drawn,  remove  the  can.  The 
remaining  process  of  securing  the  vessel  is 
of  equal  importance.  The  sides  of  the 
orifice  are  first  to  be  brought  in  apposition, 
without  pinching  them,  and  without  draw- 
ing them  from  the  vein :  the  same  cautions 
should  also  be  observed  when  the  pin  is  in- 
troduced :  let  it  be  small,  with  an  irregular 
point,  and  when  inserted  wrap  round  it  a 
few  hairs  or  a  little  tow. 

"  Common,  however,  as  this  operation  is, 
and  qualified  as  every  one  thinks  himself 
to  perform  it,  yet  there  are  very  serious  acci- 
dents which  do  arise  occasionally.  It  has 
occurred  that  the  carotid  artery  has  become 
penetrated.  When  the  puncture  has  been 
made  through  the  vein,  the  accident  is 
known  immediately  by  the  forcible  and 
pulsatory  gush  of  florid  arterial  and  dark 
venous  blood  together.  In  one  instance  of 
this  kind,  which  occurred  to  a  French  prac- 
titioner, he  immediately  thrust  his  finger 
into  the  opening  through  the  vein,  and 
thus  plugged  up  the  artery,  intending  to 
wait  for  assistance.  In  this  state  he  re- 
mained, we  believe,  an  hour  or  more ;  when, 
removing  his  finger,  to  his  surprise,  he  found 
the  haemorrhage  had  ceased,  and  did  not 
again  return.  In  another  case,  where  an 
English  practitioner  accidentally  opened 
the  carotid,  he  placed  a  compress  on  the 


orifice,  and  had  relays  of  men  to  hold  it 
there  for  eight-and-forty  iiours ;  when  it  was 
found  the  bleeding  had  stopped.  The 
admission  of  air  is  also  another  serious  ac- 
cident that  now  and  then  attends  bleeding : 
it  sometimes  happens  from  the  sudden  re- 
moval of  the  fingers  or  blood-can,  or  what- 
ever was  used  to  distend  the  vessel  by  ob- 
structing the  return  of  the  blood  :  this  being 
suddenly  taken  away,  allows  the  escape  of 
the  blood  toward  the  heart,  and  occasions 
a  momentary  vacuum,  the  air  being  heard 
to  rush  with  a  gurgling  noise  into  the  vein 
through  the  orifice  ;  it  then  mixes  with  the 
blood,  and  occasions,  in  some  instances,  al- 
most immediate  death.  The  animal  begins 
to  tremble ;  he  next  staggers,  and  finally 
falls  in  a  state  of  convulsion :  if  the  quan- 
tity of  air  taken  in  has  been  considerable, 
death  ensues.  The  remedy  must,  therefore, 
be  instantaneous,  and  consists  in  again 
opening  the  orifice,  or  making  a  new  one, 
to  gain  an  immediate  renewed  flow  of 
blood,  which  will,  in  most  cases,  renovate 
the  horse,  who  has  been  found  afterwards 
to  be  tormented  with  an  intolerable  itching. 

Opiates. —  (See  Narcotic.) 

Opium. —  A  narcotic  vegetable  poison. 
Mr.  Coleman  "  thought,  from  some  experi- 
ments made  at  the  veterinary  coUege,  that 
opium  has  no  apparent  influence  over  the 
nervous  system  of  the  horse,  and  that  it 
does  not  alleviate  pain."  Dr.  "White  says, 
"  I  think  that  opium,  as  to  its  effect  on  the 
horse,  does  not  possess  that  soothing  ano- 
dyne and  soporific  quality  for  which  it  is 
justly  distinguished  in  human  medicine." 
Opium  always  tends  to  depress  the  vital 
organs  in  proportion  to  its  quantity. 

Opodeldoc,  or  Soap  Liniment.  —  A  so- 
lution of  soap  and  camphor  in  spirits  of 
rosemary. 

Optic  Nerve.  —  The  nerve  on  which 
sight  depends. 

Orbit. — The  socket  of  the  eye  is  thus 
named. 

Organic.  —  A  disease  is  said  to  be  or- 
ganic when  any  particular  organ  of  the  body 
is  affected. 

Ossification. — Ligaments  and  cartila- 


A   DICTIONARY. 


279 


ges  sometimes  become  bony,  especially 
those  ligaments  which  unite  the  splent  to 
the  canon  bones,  and  the  lateral  cartilages 
of  the  foot. 

Ovaries. — Two  appendages  to  the  womb, 
or  uterus,  which  are  cut  out  in  the  operation 
of  spaying. 

Overreach.  —  A  horse  is  said  to  over- 
reach, or  overlash,  when  he  wounds  the  fore 
heel  with  the  hind  foot. 

Overwork.  —  Many  of  the  diseases  of 
horses  originate  in  overwork. 

Pace. —  The  peculiar  manner  of  motion, 
or  progression.  The  natural  paces  of  the 
horse  are,  the  walk,  trot,  and  gallop,  to 
which  some  add  the  amble. 

Palate.  —  The  upper  part  or  roof  of  the 
mouth. 

Palliative. —  Medicines  and  operations 
by  which  diseases  appear  to  be  relieved,  but 
not  cured.  However  desirable  palliatives 
may  be  in  the  diseases  of  the  human  body, 
they  are  seldom  satisfactory  in  the  diseases 
and  lameness  of  horses. 

Palpitation.  —  Beating  of  the  heart 
against  the  breast-bone  or  ribs. 

Palsy,  or  Paralysis. —  A  loss  of  muscu- 
lar power,  or  an  inability  to  move  any  part 
of  the  body. 

Pancreas,  or  Sweetbread. —  A  gland- 
ular substance  situated  in  the  abdomen,  near 
the  stomach.  It  secretes  the  pancreatic 
juice. 

Panniculus,  or  Fleshy  Pannicle. —  A 
thin  muscular  covering  attached  to  the  skin 
of  brute  animals,  by  means  of  which  they 
are  enabled  to  shake  it,  and  get  rid  of  flies, 
etc. 

Panton  Shoe. —  A  contrivance  for  ex- 
panding contracted  feet ;  but,  like  all  other 
mechanical  contrivances,  they  are  useless  or 
pernicious. 

Paps.  —  When  young  horses  are  cutting 
therr  teeth,  and  sometimes  after  that  period, 
the  excretory  ducts  of  some  of  the  salivary 
glands  under  the  tongue  become  enlarged. 
These  are  named  paps.  They  should  be 
touched  with  a  solution  of  alum,  and  the 
animal  fed  on  mashes.     (See  Mash.) 

Papillary.  —  Pap-like  ;    or    rather    liJce 


small  or  minute  paps.  A  term  applied  to 
small  elevations  on  different  parts  of  the 
body,  whether  morbid  or  natural.  Those 
little  eminences  on  the  internal  surface  of 
the  leaves,  or  laminae,  of  the  cow's  third 
stomach,  or  manyplus,  are  termed  papil- 
lary. 

Par  Vagum.  —  The  eighth  pair  of  nerves 
are  thus  named. 

Paracentesis.  —  The  operation  of  tap- 
ping, for  the  purpose  of  giving  vent  to  water 
collected  in  the  chest,  abdomen,  etc.  It  has 
frequently  been  performed  on  animals  with- 
out any  benefit. 

Parietal.  —  The  bones  that  form  the 
sides  of  the  skull  are  thus  named. 

Paring.  —  Cutting  the  hoof  in  order  to 
prepare  it  for  the  shoe. 

Parotid  Glands.  —  Two  large  glands 
situated  under  the  ears  ;  they  secrete  saliva, 
which  is  conveyed  by  a  duct  into  the 
mouth. 

Paroxysm.  —  The  periodical  accession, 
or  the  periodical  increase,  of  a  disorder. 

Parturition. —  The  act  of  bringing  forth 
young. 

Pastern.  —  The  part  between  the  fetlock 
joint  and  the  hoof.  (See  cut  of  the  foot, 
part  first.) 

Pastern  Nerve.  —  The  nerve  from  which 
a  portion  is  cut  out  in  the  operation  of 
nerving. 

Pasture.  —  Pastures  in  elevated  situa- 
tions are  the  best  for  horses. 

Patella.  —  The  knee-pan  of  the  human 
body,  and  the  stifle  of  the  horse.  (See 
Skeleton.) 

Pathology. —  The  doctrine  of  diseases. 

Paunch.  —  The  common  name  for  the 
first  stomach  of  the  cow. 

Pectorals.  —  Medicines  that  relieve 
cough,  and  other  diseases  of  the  lungs. 

Pectoral  Muscles.  —  The  muscles  of 
the  breast. 

Pelvis.  —  The  basin,  or  that  cavity 
wherein  is  lodged  the  bladder,  uterus,  and 
the  rectum. 

Penis. —  The  yard  or  male  genital  or- 
gan. 

Perforans    Tendon. —  The    innermost 


280 


A    DICTIONARY. 


of  the  back  sinews,  or  that  which  goes  to 
the  OS  pedis. 

PERiCAnDiuM. —  The  heart  bag.  (See 
Heart,  part  first.) 

Pericranium.  —  The  membrane  that  is 
closely  connected  with  the  bones  of  the 
head. 

Periosteum. —  The  investing  membrane 
of  the  bones. 

Peristaltic  Motion.  —  That  motion  of 
the  muscular  coat  of  the  bowels  which 
causes  the  food  and  excrement  to  pass 
through  them. 

Peritoneum. —  The  membrane  which 
forms  the  external  coat  of  the  bowels,  and 
some  other  of  the  viscera  of  the  abdomen; 
it  is,  therefore,  named  the  peritoneal  coat 
of  the  bowels.  It  lines,  also,  the  internal 
surface  of  the  belly. 

Peritonitis.  —  Inflammation  of  the  peri- 
toneum. Diseases  of  the  peritoneum  are 
very  rare  in  horses,  and,  when  treated  on 
the  depleting,  antiphlogistic  principles  of 
allopathy,  generally  terminate  fatally.  When 
the  physiological  equilibrium  is  interrupted, 
and  inflammation  of  the  peritoneum  ensues, 
the  available  vital  force  is  concentrated 
upon  a  small  region  of  the  body.  The  true 
indication  is,  to  invite  this  force  away  from 
that  region,  and  to  distribute  it  over  the 
general  system,  that  it  shall  not  be  excessive 
anywhere.  This  mode  of  relief  we  call 
equalizing  the  circulation ;  the  allopaths 
term  it  counter-irritation ;  they  concentrate 
it  in  one  spot,  in  the  form  of  rowel  and 
blister,  their  own  works  will  show  with  what 
success.*     Our  principles  teach  us  to  accom- 

*  Mr.  Percivall  details  a  case  of  peritonitis,  after  the 
usual  symptoms  in  the  early  stage  had  subsided.  "  The 
horse's  bowels  became  much  relaxed :  suspecting  that 
there  was  some  disorder  in  the  alimentary  canal,  and  that 
this  was  an  effort  of  nature  to  get  rid  of  it,  I  promoted 
the  diarrhoea  by  giving  mihl  doses  of  cathartic  medicine, 
in  combination  with  calomel ! 

"  On  the  third  day  from  this,  prolapsus  ani  (falling  of 
the  fundament)  made  its  appearance.  After  the  return 
of  the  gut,  the  animal  grew  daily  duller  and  more  de- 
jected, manifesting  evident  signs  of  considerable  inwai-d 
disorder,  though  he  showed  none  of  acute  pain.  The 
diarrhoea  continued ;  swelling  of  the  belly  and  tumefac- 
tion of  the  legs  speedily  followed.  Eight  pounds  of  blood 
were  drawn,  and  two  ounces   of  oil  of  turpentine  were 


plish  the  object  by  the  stimulating  influence 
of  medicated  vapor,  enemas,  nervines,  and 
a  mucilaginous  diet.  Whenever  the  disease 
is  treated  by  the  abstraction  of  blood,  it 
generally  terminates  in  dropsy. 

Perspiration. —  The  fluid  which  is  se- 
creted by  the  vessels  of  the  sldn.  Perspira- 
tion is  a  highly  important  discharge  in 
horses  and  other  animals.  The  best  medi- 
cine to  promote  sweating  in  the  horse  is  a 
tea  composed  of  lobelia,  capsicum,  and  pen- 
nyroyal. 

Pharynx. —  The  upper  part  of  the  oesoph- 
agus, or  gullet. 

Phlegm.  —  A  mucous  liquid  thrown  up 
from  the  lungs. 

Phrenic  Nerve. —  A  nerve  that  passes 
through  the  thorax,  over  the  heart,  to  the 
diaphragm. 

Phrenitis.  —  Inflammation  of  the  brain. 

Physic.  —  In  stable  language,  the  term 
is  applied  to  purgative  medicines. 

Physiology.  —  That  branch  of  medical 
science  which  describes  the  functions  of 
every  part  of  the  body. 

PiA  Mater.  —  A  delicate  membrane, 
that  closely  invests  the  brain. 

Pitch,  Burgundy. —  A  resin  obtained 
from  fir ;  it  is  used  in  the  composition  of 
plasters  and  charges. 

Placenta.  —  The  afterbirth. 


Plate  Vein.  —  A  large  vein  that 


runs 


from  the  inside  of  the  fore  leg  to  the  chest. 
Plethora. — A  fulness  of  vessels.  Horses 
are  often  brought  into  this  state  from  over- 
feeding, and  want  of  sufficient  exercise.  It 
is  known  by  heaviness,  dulness,  unwilling- 
ness to  work.  The  urine  is  high-colored, 
and  the  dung  generally  hard  and  slimy. 
The  cure  consists  in  the  reduction  of  the 
quantity  of  food,  warm  mashes,  and  regular 
exercise. 

given  internally,  and  in  spite  of  another  bleeding,  and 
some  subordinate  measures,  carried  him  off  [the  treat- 
ment, we  presume]  in  the  coui'se  of  a  few  hours. 

"  Dissection  :  a  slight  blush  pervaded  the  peritoneum, 
at  least  the  parietal  portion  of  it,  for  the  coats  of  the  stom- 
ach and  intestines  preserved  their  natural  whiteness. 
About  eight  gallons  of  water  were  mcasui'ed  out  of  the 
belly.  The  abdominal  viscera,  as  well  as  the  thoracic, 
showed  no  marks  of  disease." 


A     DICTIONARY. 


281 


Pleura.  —  The  membrane  which  covers 
the  lungs  so  closely  as  to  appear  a  part  of 
their  substance. 

Pleurisy,  Pleuritis.  —  Inflammation  of 
the  pleura. 

Plexus.  —  A  network  of  blood-vessels  or 
nerves. 

Pneumonia.  —  A  general  term  for  inflam- 
mation of  the  lungs. 

Poisons.  —  Articles  wliich  impede  or  de- 
stroy the  vital  operations.  Some  people 
proclaim  that  all  food  is  poison ;  that  the 
difference  in  the  effect  produced  lies  in  the 
quantity  given.  We  deny  this :  good  corn, 
oats,  and  hay,  whose  nature  is  to  nourish 
and  support  the  animal,  can  never  be  a  legit- 
imate cause  of  disease.  Its  excess  in  quan- 
tity, and  its  chemical  decomposition  for 
want  of  digestive  power,  are  all  of  true  food 
that  can  prove  injurious.  On  the  other 
hand,  experience  teaches  us  that  opium, 
arsenic,  corrosive  sublimate,  tobacco,  and 
calomel  are  inimical  to  the  animal  organ- 
ization, and  will  never  change  their  chemi- 
cal equivalents.  A  grain  of  arsenic  will 
always  be  a  grain  of  that  poison,  and  can 
be  detected  after  death :  the  same  applies 
to  opium.  A  very  few  grains  of  opium  in- 
jected into  the  carotid  artery  of  a  dog 
killed  him  in  four  minutes  ;  when  the  same 
quantity  was  injected  into  a  vein,  the  ani- 
mal lived  twenty-five  minutes.  When 
injected  into  the  bladder,  it  required  a 
larger  quantity  to  destroy  life. 

Again:  one  drop  of  the  oil  of  tobacco 
applied  on  the  tongue  of  a  rabbit  kUled  him 
instantly;  one  drop  applied  to  the  same 
organ  of  a  cat,  threw  her  into  convulsions  ; 
two  drops  placed  on  the  tongue  of  a  squirrel 
killed  it  instantly.  Hence,  it  does  not  re- 
quire much  penetration  in  order  to  decide 
what  is  and  what  is  not  poison.  Animals 
often  get,  apparently,  well,  although  large 
quantities  of  the  above  poisons  have  been 
given.  This  is  no  proof  that  the  poisons 
cured  them.  In  the  early  stage  of  the  dis- 
ease, the  constitution  can  bear  more  vio- 
lence—  blood-letting  and  poisoning  —  than 
when  it  becomes  debilitated.  This  explains 
the  reason  why  large  quantities  of  opium 

36 


may  be  given  to  a  horse  at  a  certain  time, 
without  any  perceptible  effect ;  at  another 
time,  one-half  the  quantity  will  destroy 
him. 

Poll-Evil. — An  obstinate  disease,  which 
often  happens  to  horses.  It  generally  pro- 
ceeds from  a  blow  received  upon  the  poll 
or  back  part  of  the  head. 

Porta.  —  The  name  of  the  great  vein  of 
the  liver. 

Poultice,  or  Cataplasm.  —  The  emol- 
lient poultice  may  be  composed  of  equal 
parts  of  slippery  elm  and  flaxseed.  The 
intentions  to  be  answered  by  poultices  are 
relaxation  and  stimulation.  To  relax  a  part, 
add  to  the  above  emollient,  lobelia ;  when  it 
is  necessary  to  stimulate,  use  cayenne. 
Poultices  that  are  designed  for  foul  ulcers, 
in  addition  to  the  above  articles,  should 
contain  at  least  one-third  powdered  char- 
coal. 

Prevention  or  Disease. —  It  is  an  old, 
but  true  saying,  that  prevention  is  better 
than  cure,  and,  we  may  safely  add,  less  ex- 
pensive. 

Pricks,  or  Pricking.  —  In  shoeing  a 
horse,  the  nail  is  sometimes  driven  in  a 
wrong  direction,  and  the  sensible  parts  are 
wounded ;  he  is  then  said  to  be  pricked. 
When  a  horse  has  been  slightly  pricked, 
and  the  nail  immediately  withdrawn,  it  may 
not  be  followed  by  lameness ;  but,  when 
the  wound  is  considerable,  matter  will  form ; 
if  the  matter  is  not  let  out  by  paring  away 
the  horn,  it  quickly  spreads  under  the  horny 
sole,  and  upwards  through  the  laminated 
substance  of  the  foot,  and  breaks  out  at 
the  coronet.  (See  Coronet.)  To  prevent 
this,  the  parts,  as  soon  as  the  accident  has 
happened,  should  be  bathed  with  healing 
balsam.  If  the  horse  goes  lame  for  several 
days,  a  poultice  must  be  applied  to  promote 
suppuration. 

Prim^  Vi^. —  The  first  passages,  or 
stomach,  and  first  intestines. 

Proband. —  An  instrument  for  removing 
any  obstruction  in  the  oesophagus  or  gullet. 
It  consists  of  a  rather  flexible  rod,  covered 
with  leather,  with  a  round,  smooth  knob  at 
one  end. 


282 


A    DICTIONARY. 


Probe.  —  An  instrument  for  examining 
wounds. 

Prolapsus.  —  The  falling  down  of  a  part, 
as  of  the  uterus  or  fandament. 

Psoas  Muscles.  —  The  muscles  that  lie 
under  the  loins.  These  muscles  are  some- 
times injured  in  strains  of  the  loins. 

Pulmonary  Diseases.  —  Diseases  of  the 
lungs. 

Pulmonary  Vessels.  —  The  blood-ves- 
sels and  air-vessels  of  the  lungs,  which  con- 
sist of  the  pulmonary  artery  and  vein,  and 
the  bronchia,  or  branches  of  the  windpipe. 

Pulse.  —  The  beating  of  the  arteries. 
The  horse's  pulse  is  most  conveniently  felt 
in  that  part  of  the  carotid  artery  which 
passes  under  the  angle  of  the  lower  jaw. 

PuNCTA  Lachrymalia.  —  Two  orifices 
near  the  inner  corner  of  the  eye,  through 
which  the  tears  pass. 

Pupil. —  A  part  of  the  eye. 

Pus.  —  The  white  matter  formed  by  the 
process  of  suppuration. 

Pylorus. —  The  inferior  portion  of  the 
stomach. 

Quarter  III,  or  Quarter  Evil. — 
There  is  a  variety  of  names  given  to  this 
disorder,  such  as  joint  mmTain,  or  gar- 
get, black  quarter,  quarter  evil,  black  leg, 
etc.  The  true  causes  of  this  disease  are 
generally  too  liberal  an  allowance  of  food, 
or  a  sudden  transition  from  poor  keep  to 
luxurious  and  nutritious  diet.  In  some 
cases  the  energy  of  the  body  is  lessened  by 
exposure  to  cold  and  wet ;  hence  the  quar- 
ters and  feet  swell,  and  it  is  this  circum- 
stance which  has  given  rise  to  the  name 
by  which  the  disorder  is  commonly  known. 
The  approach  of  this  complaint  is  generally 
indicated  by  the  animal  separating  himself 
from  his  companions ;  by  his  appearing 
dull,  listless,  and  heavy,  and  by  his  refusing 
food.  The  more  immediate  symptoms  are 
lameness  and  swelling  of  the  hind  quarters, 
and  occasionally  of  the  shoulders  or  back. 
These  swellings,  when  pressed,  make  a 
crackling  noise.  (See  Emphysema.)  The 
mouth  and  tongue  are  frequently  found 
blistered  in  this  disease.  A  spare  diet,  and 
keeping  the  animal  in  a  dry  barn,  are  strictly 


to  be  attended  to,  with  an  occasional  dose 
of  nitrate  of  potassa,  and  clysters  of  thin 
gruel  and  common  salt.  By  this  means 
the  disease  may  be  subdued.  If  the  dis- 
ease first  appears  in  the  foot,  a  charcoal 
poultice  must  be  applied. 

Rack  Bones.  —  The  vertebras  of  the 
back. 

Radius.  —  The  bone  of  the  fore-arm. 

Raking. —  (See  Back  Raking.) 

IJLectum. —  (See  Intestines.) 

Red- Water.  —  This  disease  often  attacks 
cows,  and  is  named  from  the  red  appear- 
ance of  the  urine. 

Respiration. — The  act  of  breathing; 
which  includes  inspiration,  or  the  taking  in 
of  air  by  the  lungs,  and  expiration,  or  the 
act  of  discharging  it. 

Ringbone.  —  A  bony  excrescence  on  the 
lower  part  of  the  pastern,  generally,  but  not 
always,  causing  lameness. 

Roaring.  —  A  disease  which  takes  its 
name  from  the  wheezing  noise  the  horse 
makes  in  breathing,  when  put  into  quick 
motion.  It  is  supposed  by  most  veterinary 
writers  to  be  caused  by  an  effusion  of  lymph 
in  the  windpipe.  Our  own  view  of  the 
subject  is,  that  it  is  owing  to  a  contraction 
of  the  respiratory  tubes. 

P^osEMARY.  —  The  essential  oil  of  this 
shrub  is  a  useful  ingredient  in  stimulating 
Liniments. 

Rot. —  A  disease  of  sheep,  resembling 
pulmonary  consumption,  complicated  with 
dropsy.  Its  causes  are  flooded  lands  and 
unsubstantial  food. 

Rowels.  —  These  are  considered  as  arti- 
ficial abscesses,  or  drains.  They  act  on  the 
principle  of  making  one  disease  to  cure 
another. 

Rumination.  —  Chewing  the  cud. 

Rupture.  —  A  swelling  caused  by  the 
protrusion  of  some  parts  of  the  bowels  out 
of  the  cavity  of  the  abdomen  into  a  kind 
of  sac,  formed  by  that  portion  of  the  peri- 
toneum (which  see)  which  is  pushed  be- 
fore it. 

Sacrum.  —  That  part  of  the  back  bone 
from  which  the  tail  proceeds. 

Saliva.  —  Spittle. 


A   DICTIONARY. 


283 


Salivation. —  A  profuse  and  continued 
flow  of  saliva. 

Sand  Crack.  —  A  perpendicular  crack  on 
the  side  or  quarter  of  the  hoof. 

Sanies.  —  A  bloody  or  greenish  matter, 
which  is  sometimes  discharged  from  foul 
ulcers. 

Sarsaparilla.  —  An  infusion  of  equal 
parts  of  sarsaparilla  and  sassafras  is  useful 
for  animals  when  the  blood  is  loaded  with 
morbific  agents. 

Scapula.  —  The  shoulder  blade. 

Scarf  Skin. —  (See  Cuticle.) 

Scarification.  —  An  incision  of  the  skin 
with  a  lancet. 

Scirrhus. —  An  indolent,  hard  tumor. 

Sclerotic  Coat. —  (See  Eye.) 

Scouring.  —  A  scouring,  or  purging,  is 
common  among  all  our  domestic  animals. 
It  is  not  a  disease,  but  only  a  symptom  of 
a  loss  of  equilibrium,  which  may  proceed 
from  improper  food,  exposure  to  the  cold  and 
rain,  which,  of  course,  includes  a  loss  of 
caloric,  or  heat.  There  is  no  general  rem- 
edy, or  one  more  speedy  and  effectual  in 
the  onset  than  mucilaginous  drinks  com- 
posed of  slippery  elm,  combined  with  injec- 
tions of  the  same.  Warmth  and  moisture 
to  the  surface,  and  antispasmodics  (which 
see),  combined  with  astringents  (bayberry 
bark  is  the  best,  in  doses  of  half  a  table- 
spoonful  every  six  hours),  will  seldom  fail 
to  effect  a  cure. 

Scratches.  —  Troublesome  sores  about 
the  heels,  depending  on  morbific  agents  in 
the  system ;  for  the  cure  of  which,  see 
"  Modern  Horse  Doctor." 

Scrotum.  —  The  bag  or  covering  of  the 
testicles. 

Secretion.  —  The  word  secretion  is  used 
to  express  that  function. 

Serum.  —  The  watery  part  of  the  blood. 

Sessamoid  Bones. —  Two  small  bones  on 
the  back  part  of  the  fetlock  joint. 

Sinew-Sprung. —  A  term  sometimes  ap- 
plied to  strains  in  the  back  sinews. 

Sitfast.  —  A  horny  kind  of  scab,  which 
forms  on  the  skin  in  consequence  of  a 
saddle-gall. 

Skin. —  (See  Cutis.) 


Slipping.  —  (See  Abortion.) 

Sole.  —  (See  Foot,  part  first.) 

Spasm.  —  An  involuntary  and  continued 
contraction  of  muscles ;  thus,  lockjaw  de- 
pends on  a  spasmodic  contraction  of  mus- 
cles. 

Spavin.  —  A  disease  of  the  horse's  hock, 
which  generally  causes  lameness.  Spavins 
are  of  two  kinds  :  the  bone,  and  the  bog  or 
blood,  spavin.  The  former  consists  of  a 
bony  enlargement  of  the  inside  of  the  hock 
joint,  towards  the  lower  part ;  the  latter,  of 
a  soft  but  elastic  tumor,  towards  the  bend 
of  the  joint.  Mr.  Percivall  remarks:  "  Not- 
withstanding our  confessed  inability  to  cure 
this  disease,  we  are  often  called  on  to  treat 
it,  as  to  the  removal  of  it  by  means  of  a 
chisel,  file,  or  saw.  Although  the  practice 
is  exceedingly  commendable  in  cases  of 
common  exostosis,  it  is  not  so  well  adapted 
to  spavin  ;  those  who  employ  such  means 
seldom  fail  to  leave  the  parts  ultimately  in 
a  worse  state  than  they  found  them.  Our 
most  successful  remedies  are  such  as  come 
under  the  denomination  of  counter-irri- 
tants." 

Spermatic  Cord.  —  The  vessels,  etc.,  by 
which  the  testicles  are  suspended,  consist- 
ing of  the  spermatic  artery  and  vein,  the 
vas  deferens,  or  seed  duct,  cremaster  mus- 
cle, and  cellular  membrane. 

Sphincter.  —  A  name  given  to  muscles 
whose  fibres  are  arranged  in  a  circular  di- 
rection, and  whose  office  is  to  shut  up  the 
parts  to  which  they  are  attached  ;  such  are 
the  sphincter  of  the  neck  of  the  bladder, 
and  the  muscles  which  close  the  funda- 
ment. 

Spine.  —  The  spine  of  the  neck  and  back 
is  composed  of  many  small  bones  named 
vertebrae.  Seven  belong  to  the  neck,  eight- 
een to  the  back,  six  to  the  loins,  five  to  the 
sacrum,  and  in  the  tail  there  are  about  thir- 
teen. 

Spleen,  or  Milt.  —  A  soft  substance,  of 
a  long,  oval  form,  and  purple  color.  It 
seems  to  be  a  reservoir  for  the  blood  that 
may  be  designed  for  the  secretion  of  bile  in 
the  liver. 

Splents.  —  These  are  bony  excrescences, 


284 


A  DICTIONARY. 


which  grow  on  the  inside  of  the  shank 
bone. 

Staggers. —  This  is  named  from  the 
staggering  gait  of  the  animal.  It  may  be 
brought  on  by  the  horse  eating  too  greedily, 
swallowing  his  food  when  imperfectly 
chewed,  or  eating  freely  of  food  that  is  dif- 
ficult of  digestion.  Horses  of  rather  an  ad- 
vanced age,  and  weak  digestive  organs, 
when  improperly  fed,  or  when  a  large  quan- 
tity of  meal  is  allowed,  are  very  liable  to 
apoplexy,  or  staggers.  The  disease  is  gen- 
erally symptomatic  of  derangement  of  the 
stomach,  indigestion,  and  over-distention  of 
the  digestive  organs. 

Sternum.  —  The  breast  bone. 

Stifle  Joint. —  This  joint  is  composed 
of  the  bones  called  os  femoris,  tibia,  and 
patella.     (See  Skeleton.) 

Stopping.  —  A  mixture  of  clay  and  cow- 
dung  is  employed  for  the  pm-pose  of  stop- 
ping horses'  feet,  and  keeping  them  moist. 

Strains.  —  For  all  lands  of  strains,  rest 
is  the  best  remedy  ;  sometimes  they  require 
poultices,  fomentations,  etc.  The  latter 
will  be  indicated  by  pain  and  swelling. 

Stubs.  —  When  a  horse  is  wounded  by 
a  splinter  of  wood,  about  the  foot  or  leg,  he 
is  said  to  be  stubbed. 

Styptics.  —  Medicines  which  stop  bleed- 
ing. The  most  effectual  method  of  stopping 
bleeding  is  to  tie  the  wounded  vessel. 

SuDORiFics.  —  Medicines  which  excite 
sweating.  It  is  very  difficult  to  sweat  a 
horse,  except  the  process  be  assisted  by 
warmth  and  vapor  -externally.  Lobelia, 
pennyroyal,  and  capsicum,  promote  the  in- 
sensible perspiration  ;  they  must  be  given 
in  infusion  to  the  amount  of  half  a  gallon 
or  more. 

Sulphur.  —  Used  in  cutaneous  diseases, 
as  an  alterative. 

Sweetbread.  —  (See  Pancreas.) 

Synovia,  Joint  Oil.  —  A  mucilaginous 
fluid  formed  within  joints,  to  render  motion 
easy,  or  diminish  friction. 

Tansy. —  A  medicine  used  to  expel 
worms. 

Tar.  —  Common  tar  is  used  as  an  astrin- 
gent for  horses'  feet. 


Tartar,  Cream  of.  —  Used  on  horses  to 
promote  the  secretion  of  urine. 

Tenaculum.  —  A  kind  of  hook,  for  taking 
up  an  artery. 

Tendo  Achillis. —  The  great  tendon, 
which  is  fixed  or  inserted  into  the  calca- 
neum,  or  projecting  bone  of  the  hock. 

Tendon.  —  The  white  shining  extremity 
of  a  muscle. 

Tenesmus.  —  Continual  efforts  to  void 
dung,  without  any  discharge. 

Tent.  —  A  piece  of  lint,  or  tow,  smeared 
with  ointment,  and  thrust  into  a  sore,  in 
order  to  prevent  a  too  hasty  and  superficial 
healing. 

Thoracic  Duct.  —  The  trunk  of  the  ab- 
sorbents.    (See  Absorbents,  part  first.) 

Thrush.  —  A  disease  has  lately  prevailed 
to  a  great  extent  in  the  New  England  States, 
which  deserves  some  consideration.  It  is 
called  thrush,  and  is  supposed  to  be  a  dis- 
ease of  the  horse's  frog,  consisting  in  a  dis- 
charge of  matter  from  its  cleft,  or  division ; 
sometimes  the  other  parts  of  the  frog  are 
also  affected,  —  become  soft,  ragged,  and 
incapable  of  affording  protection  to  the 
sensitive  frog,  which  it  covers.  We  cannot 
agree  with  many  writers,  that  thrush  is  a 
strictly  local  disease  ;  for,  after  it  has  passed 
through  the  different  stages,  viz.,  inflamma- 
tion, suppuration,  etc.,  the  whole  system 
takes  up  the  diseased  action,  either  by  sym- 
pathy or  irritation.  Hence  the  reader  \vUl 
see  the  folly  of  depending  on  local  agents, 
in  the  form  of  ointments,  for  the  cure  of  the 
disease,  in  which  all  the  organs  are  more  or 
less  concerned. 

The  internal  remedies  we  recommend, 
are  alteratives;  remove  the  cause,  if  any 
exist,  in  the  form  of  bad  ventilation,  poor 
diet,  hard  work,  partial  grooming,  or  the 
sluicing  of  cold  water  on  the  legs.  Let 
the  animal  have  bran  mashes,  with  a  few 
boiled  carrots,  every  night. 

The  local  remedies  consist  in  paring 
away  the  ragged  or  uneven  parts  of  the  frog ; 
then  wash  the  surface  with  castile  soap  and 
lukewarm  water ;  afterwards  with  a  solution 
of  common  salt,  in  the  following  propor- 
tions :  one  tablespoonful  Liverpool  salt  to 


A  DICTIONARY. 


285 


a  pint  of  rain  water ;  then  apply  linseed 
oil,  spirits  of  turpentine,  pyroligneous  acid, 
—  equal  parts,  —  in  the  cleft  of  the  frog  ; 
let  the  whole  surface  be  covered  with  tow, 
then  upon  the  tow  place  a  flat  piece  of 
wood,  about  the  width  of  the  frog,  —  one 
of  the  ends  passing  under  the  toe  of  the 
shoe,  the  other  extending  to  the  back  part 
of  the  frog,  and  bound  down  by  transverse 
slips  of  wood,  the  ends  of  which  are  to  be 
placed  under  the  shoe.  The  moderate  pres- 
sure thus  applied  will  contribute  materially 
to  the  cure  and  to  the  production  of  solid 
horn.  This  dressing  must  be  repeated  daily. 
If,  after  this  treatment,  matter  should  dis- 
charge, the  heel  contract,  and  the  horn 
soften,  then  apply  a  poultice  of  Indian  meal, 
with  half  a  tablespoonful  of  cayenne  pep- 
per on  the  sm-face,  washing  the  foot,  as 
above,  every  night. 

Tibia.  —  The  bone  of  the  horse's  thigh  ; 
that  is,  the  bone  between  the  hock  and  the 
stifle. 

Ticks.  —  Insects  that  infest  sheep  and 
other  animals.  A  strong  infusion  of  lobe- 
lia will  destroy  them. 

ToiNGUE. —  The  tongue  is  a  muscular 
substance,  composed  of  fibres  variously  ar- 
ranged, by  which  it  is  rendered  capable  of 
that  diversity  of  action  which  we  observe  ; 
it  has  also  several  muscles  attached  to  it. 
The  small  bone,  to  which  it  has  a  muscular 
attachment,  is  named  os  hyoides. 

Tonics. —  Medicines  that  augment  the 
strength  of  the  body,  such  as  gentian,  wild 
cherry,  poplar  bark,  etc. 

Training.  —  By  the  word  training  is 
meant,  putting  a  horse  in  that  state  in 
which  all  the  functions  of  the  body  are  in 
equilibrium.  In  order  to  bring  a  horse  into 
this  desirable  state,  we  refer  the  reader  to 
the  "  Modern  Horse  Doctor." 

Tubercles. —  Small  tumors  that  some- 
times suppurate  and  discharge  pus ;  they 
are  often  found  in  the  lungs. 

Tumor. —  A  swelling  on  any  part  of  the 
body.  Tumors  are  of  various  kinds  :  some- 
times caused  by  bruises,  or  other  accidents ; 
at  others,  arising  without  any  visible  cause. 

Tunic. —  A  coat,  or  membrane,  investing 


a  part ;  such  as  the  tunica  vaginalis  of  the 
testicles. 

TuRGEscENCE. —  An  over-fulucss  of  the 
vessels  in  any  part. 

Tumeric.  —  Tumeric  root,  an  aromatic 
stimulant,  sometimes  used  in  jaundice  or 
yellows. 

Twitch.  —  An  instrument  made  by  fix- 
ing a  noose,  or  cord,  to  the  end  of  a  stick  ; 
this  is  put  on  the  horse's  upper  lip  and 
twisted  rather  tight,  which  makes  him  stand 
quiet  dm'ing  an  operation. 

Tympany.  —  A  distention  of  the  abdo- 
men by  air. 

Typhus.  —  Putrid  fever. 

Udder.  —  The  udder  is  a  glandular  body, 
whose  ofiice  is  to  secrete  milli.  It  is  di- 
vided, in  the  cow,  into  four  quarters  ;  each 
of  which  has  an  excretory  duct,  or  teat, 
whose  office  is  to  facilitate  the  extraction 
of  milk.  At  the  extremity  of  each  teat  is 
a  contrivance  for  the  purpose  of  retaining 
the  fluid  contained  in  the  udder,  until  it  be- 
comes much  distended  ;  when,  if  not  drawn 
off",  it  flows  spontaneously,  and  the  animal 
is  thereby  partly  relieved  of  her  burden. 
Sometimes  the  udder  swells  and  becomes 
sore,  as  is  often  caused  by  improper  feed- 
ing. As  there  is  great  sympathy  existing 
between  the  stomach  and  udder,  whatever 
deranges  the  former  wiU  also  affect  the  lat- 
ter, through  the  medium  of  sympathetic 
action.  In  this  case,  the  cow  should  be 
drenched  with  a  tea  of  pennyroyal  and  thor- 
oughwort,  and  fed  on  gruel.  The  udder 
should  be  fomented  with  an  infusion  of 
mullen  leaves.  Should  the  swelling  con- 
tinue, and  appear  painful,  the  following 
embrocation  may  be  used  :  linseed  oil  and 
lime-water,  equal  parts,  mix.  If  an  abscess 
forms,  and  matter  can  be  felt,  it  should  be 
opened  at  its  most  depending  part,  so  that 
the  matter  may  run  freely  off". 

Ulcers.  —  There  are  quite  a  variety  of 
ulcers  to  be  found  in  animals ;  the  most  of 
them  will  heal  by  the  application  of  a  mild 
astringent,  or  tonic,  such  as  an  infusion  of 
bayberry  bark,  or  the  tincture  of  capsicum. 
If  it  be  foul  or  callous  in  any  part,  then 
powdered  bloodroot  will  be  proper. 


286 


A    DICTIONARY. 


Ureters.  —  Two  small  tubes  by  which 
the  urine  is  conveyed  from  the  Iddneys  to 
the  bladder. 

Urethra. —  A  membranous  and  muscu- 
lar tube  by  which  the  urine  is  conveyed  from 
the  bladder ;  it  is  of  considerable  length  in 
the  horse. 

Urine,  Excessive  Discharge  of.  —  (See 
Diabetes.) 

Urine,  Incontinence  of. —  (See  Incon- 
tinence.) 

Uterus.  —  The  womb.  The  uterus  of 
the  mare  is  very  unlike  that  of  the  human 
subject,  in  whom  it  consists  of  one  bag, 
rather  of  an  oval  shape,  somewhat  resem- 
bling a  pear ;  but  in  the  mare  and  other  quad- 
rupeds it  has  a  body  and  two  branches, 
called  its  horns.  The  uterus  terminates  in 
the  vagina  by  a  narrow  portion,  called  the 
neck  or  mouth  of  the  womb.  The  extrem- 
ities of  these  horns  have  tubes  attached  to 
them,  which,  from  the  name  of  the  discov- 
erer, are  called  Fallopian  tubes ;  one  end 
of  each  is  expanded,  and  has  a  fringed  kind 
of  edge  :  this  is  named  the  fimbria  of  the 
Fallopian  tube.  The  Fallopian  tube  is 
very  tortuous  in  its  form  ;  and  that  end 
which  proceeds  from  the  horn  of  the  uterus 
is  extremely  small ;  but  the  other,  which  is 
slightly  attached  to  the  ovarium,  is  consid- 
erably larger.  The  ovarium  is  an  oblong 
body,  about  the  size  of  a  small  hen's  egg. 
The  ovaria  —  for  there  are  two  of  them  — 
are  composed  of  a  number  of  transparent 
vesiculae,  called  ova  (eggs) ;  each  ovum  is 
surrounded  with  cellular  membrane;  and 
when  the  ovum  is  impregnated  and  passes 
into  the  uterus,  it  leaves  a  mark  which  is 
named  corpus  luteum. 

Uvula.  —  In  the  human  subject,  the 
small  flesh-like  substance  hanging  in  the 
middle  and  back  part  of  the  throat,  is  thus 
named.  In  the  horse,  this  is  of  a  very  dif- 
ferent form.  The  uvula  completely  closes 
the  opening  to  the  pharynx,  though  it  read- 
ily yields  to  the  passage  of  food,  or  any 
liquid,  toward  the  gullet ;  it  prevents,  also, 
the  return  of  anything  to  the  mouth,  even 
the  air  which  is  expired  from  the  lungs,  un- 
less it  be  thrown  aside  by  a  violent  effort. 


as  in  coughing.  It  is  on  this  account  that, 
when  the  horse  is  affected  with  nausea,  or 
has  the  action  of  the  stomach  inverted,  — 
which  sometimes  happens,  though  very 
rarely,  —  the  contents  of  the  stomach  will  be 
discharged  through  the  nostrils ;  but  if  the 
horse  happens  to  cough  during  the  process, 
some  part  will  be  discharged  by  the  mouth. 

Vagina.  —  The  passage  from  the  external 
pudendum,  or  shape,  to  the  mouth  of  the 
womb. 

Valerian. —  The  root  of  valerian  is  used 
as  an  antispasmodic ;  its  virtues  have  been 
underrated  by  writers  on  veterinary  medi- 
cine. 

Veins.  —  The  motion  of  the  heart  is 
known  to  communicate  momentum  to  the 
blood  through  the  veins.  INIr.  Percivall 
says  :  "  We  are  not  to  reject  the  power  of 
the  heart  altogether,  merely  because  the 
blood  flows  with  a  uniform  stream  in  the 
veins ;  for  the  absence  of  pulsation  in  them 
is  no  proof  that  the  motion  of  the  blood  is 
not  influenced  by  the  contractions  of  the 
heart ;  the  extreme  division  which  this  fluid 
undergoes  in  its  circulation  through  the 
capillaries,  and  the  tortuosity  and  complica- 
tion of  the  numberless  small  veins,  account 
for  the  regular  and  uninterrupted  stream 
which  we  meet  with  in  the  larger  branches. 
To  prove  that  this  is  the  explanation  of  the 
fact,  if  you  open  a  vein  that  has  free  and 
direct  communication  with  the  extremity 
of  an  artery  (its  capillary  structure),  the 
blood  wiU  flow  from  it  with  the  same  pul- 
satory motion  as  if  the  artery  itself  had 
been  penetrated  :  but  if  the  vein  be  one  of 
large  size,  remotely  situated  from  any  arte- 
rial communication,  or  if  it  be  one  that 
springs  from  the  union  of  numerous  capil- 
laries, that  smooth  and  even  stream,  with 
which  the  blood  circulates  in  the  trunks, 
will  be  observable  here.  These  facts,  then, 
lead  us  to  conclude  that  the  force  of  the 
heart  is  not  sufficient  of  itself  to  propel 
blood  through  the  venous  system." 

From  the  collected  accounts  of  writers 
on  this  subject,  it  seems  highly  probable, 
that  the  blood  flowing  in  the  veins  receives 
additional  momentum  from  the  reaction  of 


A   DICTIONARY. 


287 


the  capillaries,  and  that  it  is  further  urged 
on  by  some  contractile  force  resident  in 
these  vessels  themselves.  That  the  blood 
is  advanced  in  its  course  by  the  action  of 
those  muscles  contiguous  to  veins  furnished 
with  valves,  is,  without  doubt,  well  founded, 
as  far  as  an  occasional  auxiliary  is  con- 
cerned, as  the  common  operation  of  bleed- 
ing demonstrates ;  for  it  is  in  consequence 
of  muscular  pressm*e  upon  the  veins  about 
the  head,  that  the  motion  of  a  horse's  jaw 
accelerates  the  flow  of  blood  through  the 
jugular  vein:  as  such,  however,  it  cannot 
be  ranked  among  the  essential  cavises  of 
the  blood's  motion  in  them. 

Ventricle. —  One  of  the  cavities  of  the 
heart.     (See  Heart.) 

Vermifuge. —  Medicines  that  destroy  or 
expel  worms. 

Vertebra.  —  The  bones  of  the  neck 
and  spine. 

Vertigo.  —  A  slight  degree  of  apoplexy. 

Viscera.  —  The  plural  of  viscus,  a  term 
applied  to  the  internal  organs,  as  the  lungs, 
bowels,  etc. 

Vives.  —  A  swelling  of  the  parotid  gland, 
which  is  situated  between  the  ear  and  the 
angle  of  the  jaw. 

,     Vulva.  —  A  name  given  to  the  external 
parts  of  generation  in  females. 

Wall  Eyes.  —  A  horse  is  said  to  have 
a  wall  eye,  when  the  iris  is  of  a  light  or 
white  color. 

Warbles.  —  Small,  hard  swellings  on  the 
horse's  back,  caused  by  the  pressure,  or 
heat,  of  the  saddle. 

Warts.  —  Spongy  excrescences  which 
arise  in  various  parts  of  the  body. 

Wens.  —  Hard  tumors,  of  various  sizes, 
in  different  parts  of  the  body.  The  most 
effectual  method  of  removing  them  is  to  dis- 
sect them  out,  together  with  the  cyst,  or 
bag,  in  which  they  are  formed.  The  skin 
is  then  to  be  sutured,  and  treated  as  a  com- 
mon wound. 

Whirl  Bone,  or  Round  Bone. —  The 
hip  joint  is  thus  named. 

Wind.  —  The  most  effectual  method  of 
bringing  a  horse  to  his  wind,  is  to  give  him 
regular  exercise. 


WiNDGALLS. —  Elastic  tumors  on  each 
side  of  the  back  sinews,  immediately  above 
the  fetlock  joint ;  they  are  often  caused  by 
hard  work,  or  trotting  on  hard  roads,  at  too 
early  an  age.  There  are  various  operations 
recommended,  such  as  firing,  blistering,  etc.; 
but  the  remedy  is  generally  worse  than  the 
disease.  E-est,  bandaging,  and  the  occa- 
sional use  of  liniment,  is  all  that  can  be 
done  with  safety. 

Withers.  —  The  part  where  the  mane 
ends  is  thus  named  in  the  horse. 

Worms. —  The  stomach  and  bowels  of 
horses  are  liable  to  be  infested  with  different 
kinds  of  worms  ;  but  as  the  same  treatment 
is  proper,  of  whatever  kind  they  may  be,  it 
is  needless  to  enter  into  a  particular  descrip- 
tion of  them.  Many  articles  are  recom- 
mended by  veterinary  writers,  for  the  pur- 
pose of  ridding  the  animal  of  these  pests, 
viz.,  antimony,  calomel,  turpentine,  either  of 
which  would  be  just  as  likely  to  kill  the 
horse  as  the  worms.  The  true  indications 
to  be  fulfilled  are  to  tone  up  the  stomach 
and  digestive  organs.* 

Yard,  Fallen. —  (See  Falling  of  the 
Yard.) 

Yard,  Foul.  —  The  horse's  penis  some- 
times requires  to  be  washed  with  soap  and 
water,  in  order  to  free  it  from  mucous 
matter  and  dirt. 

Yellows.  —  This  disease  is  indicated  by 
a  yellowness  of  the  membranes  that  line 
the  eyelid,  and  the  inner  parts  of  the  lips 
and  mouth.  In  this  disease,  the  natural 
course  of  the  bile  is  perverted ;  it  becomes 
absorbed  into  the  circulation,  and  thus 
tinges  the  membranes  and  fluids  of  a  yel- 
low color.  The  excrement  is  generally  of  a 
lighter  color  than  usual.  The  disease  may 
be  produced  by  a  want  of  tone  in  the  liver, 
caused  by  obstructing  the  surface. 

*  Dr.  J.  Hinds  says,  "  Since  the  worms  are  not  always 
to  be  killed,  oven  by  strong  poisons  (calomel),  nor  brought 
away  by  brisk  purgatives,  reason  dictates  and  nature 
beckons  us  to  follow  her  course  in  affording  to  the  horse  a 
run  at  grass ;  if  that  is  impossible,  adopt  the  means  nearest 
thereto  that  lie  within  our  reach."  If  calomel  is  a  poison, 
—  and  thousands  declare  it  is,  —  then  it  must  entail  a 
disease  more  formidable  than  the  one  it  is  intended  to  cure. 


c3 


APPENDIX    TO    PART    FIRST. 


LIGAMENTARY  MECHANISM   OF 
ARTICULATIONS. 

ARTICULATIONS    OF    THE    TRUNK. 

Ligaments  of  the  spine.  —  Those  between 
the  head  and  first  and  second  vertebrsB  are: 

Lateral  ligaments,  one  on  each  side,  that 
run  from  the  coronoid  processes  of  the  occi- 
pital bone  to  the  fore  part  of  the  atlas,  and 
are  fixed  in  the  roots  of  the  transverse  pro- 
cesses. 

Suspensory  ligament  of  the  head  is  a  broad 
ligament  enclosed  within  the  capsular.  It 
proceeds  from  the  body  of  the  atlas  to  the 
occipital  bone. 

Capsular  ligament  is  attached  to  the  occi- 
pital bone,  around  the  roots  of  the  condy- 
loid process,  and  to  the  anterior  articular 
processes  of  the  atlas. 

Superior  ligament  runs  from  the  long  ring 
of  the  atlas  to  the  spine  of  the  vertebra 
dentata. 

Odontoid  ligaments  are  three  in  number : 
the  two  long  pass  from  the  sides  of  the 
process  dentata  to  the  occipital  condyles ; 
the  last  runs  from  the  point  of  that  process 
to  the  anterior  and  inferior  parts  of  the 
atlas. 

Inferior  ligament  runs  from  the  inferior 
spinous  process  of  the  first  to  the  second 
vertebra. 

The  ligaments  common  to  the  spine  are : 

Intervertebral  ligaments.  —  They  are  the 
chief  bond  of  union  by  which  one  vertebra 
is  bound  to  another. 

The  common  inferior  and  superior  liga- 
ments. —  The  former  passes  obliquely  along 
the  inferior  parts  of  the  vertebree,  and  the 
latter  runs  within  the  spinal  canal. 

Capsular  ligaments  sm-round  the  smooth 

37 


cartilaginous  surfaces  of  the  articulatory 
processes. 

Intertransverse  ligaments  fix  the  trans- 
verse processes  of  the  dorsal  vertebree  to- 
gether. 

Interspinous  ligaments  are  found  between 
the  spinous  processes  of  the  back  and  loins. 

Ligamentmn  subjlavum  (or  nuchse)  ex- 
tends from  the  occipital  bone  to  the  tail.  It 
covers  and  connects  the  spinous  processes 
of  the  back,  loins,  sacrum,  and  coccyx. 
This  ligament  forms  a  strong  connecting 
medium  between  the  spines  of  the  ver- 
tebras. 

Ligaments  of  the  pelvis.  —  Two  superior 
transverse  ligaments  are  fixed  to  the  trans- 
verse processes  of  these  bones  above ;  two 
inferior,  below,  run  from  the  fourth  and  fifth 
transverse  processes  of  the  loins  to  the  crest 
of  the  ileum.  Sacro-iliac  symphysis  con- 
sists of  a  cartilago-ligamentous  substance 
interposed  between,  and  firmly  adherent  to, 
the  transverse  processes  of  the  sacrum  and 
the  inward  part  of  the  ileum.  This  union 
is  strengthened  by  ligamentary  bands,  which 
run  from  the  posterior  spine,  and  border  of 
the  ileum,  to  the  transverse  process  of  the 
sacrum. 

Sacro'Sciatic  ligaments  are  broad  expan- 
sions stretched  across  the  sacro-sciatic 
notch.  They  arise  from  the  transverse  pro- 
cesses of  the  sacrum,  and  those  of  two  or 
three  uppermost  bones  of  the  coccyx,  and 
are  extended  to  the  posterior  parts  of  the 
ileum  and  ischium,  and  to  the  tuberosity 
of  the  latter. 

Obturator  ligament  is  an  expansion,  thin- 
ner than  the  last,  wliich  passes  across  the 
foramen  magnum  ischii. 

Ligament  of  the  symphysis  is  the  carti- 

(2S9> 


290 


APPENDIX   TO   PART   FIRST. 


lago-ligamentous  substance  which  unites  the 
pubic  bones. 

Ligaments  of  the  ribs. —  Every  rib  is  con- 
nected to  two  vertebrsB  by  four  ligaments, 
viz.,  two  capsular,  internal  and  external  lig- 
aments. 

Capsular  ligament  of  the  head  invests  and 
holds  it  within  the  vertebral  socket.  Two 
articular  cavities  are  found  within  it,  one 
with  each  vertebrse,  which  have  separate 
synovial  linings. 

Capsular  ligament  of  the  tubercle  sur- 
rounds it  at  its  articulation  with  the  trans- 
verse process  of  the  vertebra. 

External  and  internal  ligaments  consist 
of  strong  fibres,  which  connect  the  neck  of 
the  rib,  above  and  below,  to  the  spine. 

Intercostal  ligaments  are  broad  fibrous 
bands  which  run  obliquely  across  the  inter- 
costal spaces,  and  hold  the  ribs  and  their 
cartilage  firmly  together. 

Sternal  ligaments.  —  These  several  pieces 
of  the  breast  bone  are  united  to  each  other 
by  intervening  cartilaginous  substance ;  in 
addition  to  wliich  they  are  connected  by 
ligamentary  bands,  both  inwardly  and  out- 
wardly. The  fore  part  of  it  is  surmounted 
by  a  broad  portion  of  cartilage,  which  runs 
along  its  under  part. 

ARTICULATIONS    OF    THE    FORE    EXTREMITY. 

Shoidder  joint.  —  The  capsular  ligament 
around  this  joint  is  strengthened  in  many 
places  by  additional  fibres  dispersed  upon 
its  exterior.  It  is  fixed  to  the  rough  margin 
of  the  glenoid  cavity,  and  to  the  neck  of 
the  OS  humeri.  A  synovial  membrane  lines 
it,  which  may  be  followed  upon  the  carti- 
laginous surfaces  of  the  bones.  Externally, 
this  ligamentous  capsule  is  clothed  on  every 
side  by  muscles,  and  to  them  is  attributed 
the  main  strength  of  the  joint. 

Elboiv  joint.  —  The  ligaments  of  it  are 
two  lateral  and  a  capsular. 

Kiiee  joint.  —  In  the  knee  there  are  five 
distinct  articulations ;  one  between  the  ra- 
dius and  the  three  small  bones  of  the  upper 
row;  a  second  between  the  small  bones, 
above  and  below ;  a  third  between  those 
of  the  lower  row  and  the  metacarpal  bones; 
a  fourth  between  the  os  h-apezium  and  the 


OS  cuneiforme;  and  a  fifth  between  the  os 
pisiforme  and  os  trapezoides ;  they  have  all 
separate  capsular  ligaments  and  synovial 
linings. 

The  ligaments  of  the  knee,  and  the  ten- 
dons passing  over  it,  are  girt  by  broad, 
glistening,  ligamentous  bands,  which  retain 
the  latter  in  their  places,  and  render  the 
joint  stronger  and  more  compact.  Between 
these  ligaments,  fascia,  and  the  extensor 
tendons,  are  some  small  bursas. 

External  lateral  ligament  runs  from  a 
tubercle  upon  the  radius  to  the  head  of  the 
external  metacarpal  bone. 

Internal  lateral  ligament  consists  of  two 
parts,  which  proceed  from  a  similar  tubercle 
upon  the  inside,  and  from  the  body  of  the 
radius.  The  longer  is  fixed  to  the  inner 
head  of  the  metacarpal  bone,  and  the 
shorter  to  the  fore  part  of  the  metacarpal. 

Ligamentum  anmdare  passes  from  the  os 
trapezium  to  the  ossa  scaphoides  and  cunei- 
forme :  it  confines  the  flexor  tendons. 

Fetlock  joint.  —  Capsular  ligament  is  at- 
tached to  the  articulatory  surfaces  of  these 
bones;  and  the  synovial  membrane,  after  hav- 
ing lined  it,  is  reflected  upon  their  cartilages : 
it  is  guarded  in  front  by  the  extensor  tendon. 

Long  lateral  ligament  is  fixed  to  a  projec- 
tion upon  the  side  of  the  metacarpal  bone, 
and  to  the  os  suifraginis. 

Short  lateral  ligament  runs  underneath 
the  latter.  These  ligaments  prevent  motion 
sideways. 

The  ligaments  of  the  sessamoid  bones 
are  seven,  viz.:  superior  suspensory,  the 
long  inferior,  the  short  inferior,  the  two  lat- 
eral, and  the  two  crucial. 

Pastern  joint  is  formed  by  the  adaptation 
of  the  ossa  suffraginis  and  corona.  It  has  a 
capsular,  and  two  pairs  of  lateral  ligaments. 

The  capsular  ligament  is  inserted  into  the 
smooth  cartilaginous  ends  of  these  bones  : 
it  is  blended  with  the  extensor  tendon  in 
front,  and  behind  with  the  long  inferior  lig- 
aments of  the  sessamoids. 

The  lateral  ligaments  are  inserted  on  the 
sides  of  the  os  coronas  and  suffraginis. 

Coffin  joint  is  made  up  of  three  bones : 
the  03  corona,  pedis,  and  naviculare. 


LIGAMENTARY  SYSTEM. 


291 


Capsular  ligament  envelopes  the  articula- 
tory  surfaces,  and  is  inserted  beyond  their 
limits ;  in  front  it  is  united  with  the  exten- 
sor tendon ;  behind,  it  is  sti'engthened  by 
the  tendo  perforans.  In  addition  to  the 
capsular,  there  are  three  pairs  of  ligaments. 

Tlie  first  pair  passes  from  the  superior 
edges  of  the  os  pedis  to  the  lateral  parts  of 
the  OS  corona,  and  are  inserted  about  its 
middle. 

The  second  pair  is  stretched  from  the  ex- 
tremities of  the  OS  pedis  to  the  os  corona, 
and  are  fixed  below  and  behind  the  first. 

Third  pair  arise  from  the  sides  of  the 
coronal  process,  and  terminate  in  the  car- 
tilages. 

The  ligaments  of  the  os  naviculare  are 
four,  viz. :  two  single,  and  one  pair. 

Superior  ligament  runs  from  its  upper 
and  posterior  part  to  the  tendo-perforans. 

Inferior  is  a  very  broad  ligament,  arising 
from  the  whole  of  the  lower  edge  of  the 
bone,  and  thence  extending  to  the  os  pedis, 
above  the  long  extensor  tendon. 

Lateral  ligaments  fix  the  os  naviculare, 
by  its  two  ends,  to  the  sides  of  the  os 
corona. 

ARTICULATIONS    OF    THE    HIND    EXTREMITY. 

The  thigh  joint  is  formed  by  the  reception 
of  the  head  of  the  os  femoris  into  its  socket. 

Capsular  ligament  is  attached  around  the 
cervix  of  the  os  femoris  and  the  margin  of 
the  acetabulum ;  it  is  thickly  clothed  on 
every  side  by  muscle,  which  assists  to  main- 
tain its  position. 

The  acetabulum  is  surrounded  by  the 
circular  ligament,  whose  border  turns  in- 
ward to  embrace  the  cartilaginous  head  of 
the  OS  femoris. 

The  notch  in  this  cavity,  to  its  inward 
side,  is  crossed  by  the  transverse  ligament, 
which  here  makes  up  for  the  deficiency  in 
the  bone. 

Ligamentum  teres  consists  of  a  bundle  of 
ligamentous  fibres  inclosed  in  a  sheath, 
which  proceed  from  a  pit  in  the  inner  and 
upper  part  of  the  ball  to  a  similar  one  in 
the  roof  of  the  socket.  Another  portion  of 
it  leaves  the  cavity  under  the  transverse 
ligament,  and  is  implanted  in  the  pubes. 


The  synovial  membrane  lines  the  socket, 
and  is  reflected  over  these  parts. 

Stifie  joint  is  composed  of  the  os  femoris, 
the  tibia,  and  patella. 

Ligamenta  patella  are  composed  of  four 
strong  cords,  which  descend  over  the  con- 
dyles of  the  OS  femoris,  and  are  inserted 
into  the  tubercle  of  the  tibia.  The  external 
one  passes  upon  the  outer  and  anterior 
part  of  the  external  condyle ;  the  internal, 
upon  the  inward  part  of  the  internal  con- 
dyle ;  and  the  middle  one,  between  them. 
They  approach  each  other  in  their  descent. 
Concealed  by  the  external  one  is  the  fourth 
ligament  of  the  pateUa ;  it  runs  to  the  out- 
ward part  of  the  tibia. 

The  patella,  with  its  articulatory  surface 
of  the  condyles  in  front,  forms  a  joint  of  its 
own,  perfectly  distinct  from  that  between 
the  tibia  and  os  femoris. 

Its  capsular  ligament  is  fixed  to  its  sur- 
rounding border. 

Internal  lateral  ligament  descends  from 
the  internal  condyle  to  the  inner  and  upper 
part  of  the  tibia. 

External  lateral  ligament  —  stronger  than 
the  internal  —  runs  from  the  external  con- 
dyle to  the  upper  end  of  the  fibula. 

Crucial  ligaments,  short  and  strong,  and 
deeply  buried  within  the  joint,  run  from  the 
space  within  the  condyles  to.  the  tibia. 

The  synovial  membrane,  after  having 
lined  the  capsule,  is  reflected  upon  the  car- 
tilages and  ligaments  included  within  it. 

Hock  joint  has  four  lateral  ligaments, 
two  on  each  side,  called  internal  and  exter- 
nal. 

Capsular  ligament  includes  the  lower  end 
of  the  tibia,  and  the  pully-lilvc  part  of  the 
astragulus;  to  both  of  which,  and  the  lat- 
eral ligaments,  and  to  the  os  calcis,  it  is 
firmly  attached. 

The  OS  calcis  forms  a  joint  with  the  os 
cuboides,  and  the  ossa  cuneiforme  are  also 
a  joint,  and  the  middle  and  small  bones 
make  joints  with  the  cuboid  above,  and  the 
metatarsi  below ;  hence,  there  are  six  artic- 
ulations in  addition  to  what  we  commonly 
understand  by  the  hock  joint,  that  between 
the  tibia  and  astragulus. 


Webster  Family  Library  of  Veterinary  Medicine 
CumnninQS  School  of  Veterinary  Medicine  at 
Tufts  University 


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